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C1 verb /ɪnˈvælɪdeɪt/

invalidate

ungültig machen
Meaning
To make something not valid or legally acceptable.
Example
The new evidence may invalidate the previous ruling.
Die neuen Beweise könnten das vorherige Urteil ungültig machen.
C1 adjective /ɪnˈsɛp(ə)rəbəl/

inseparable

unzertrennlich
Meaning
Unable to be separated or always together.
Example
The two friends have been inseparable since childhood.
Die beiden Freunde sind seit ihrer Kindheit unzertrennlich.
C1 noun /ˌɪməˈtjʊərəti/

immaturity

Unreife
Meaning
the state of not being fully developed emotionally, mentally, or physically; lack of maturity
Example
His immaturity made it difficult for him to handle responsibility.
Seine Unreife machte es ihm schwer, Verantwortung zu übernehmen.
C1 adjective /ˌɪndɪˈstɪŋkt/

indistinct

undeutlich
Meaning
Not clear or sharply defined; vague or blurred.
Example
The sound of voices was indistinct in the distance.
Der Klang der Stimmen war in der Ferne undeutlich.
C1 verb /ˈɪtəreɪt/

iterate

iterieren
Meaning
To repeat a process or statement, often to improve or refine.
Example
The software team will iterate the design until it meets user needs.
Das Softwareteam wird das Design iterieren, bis es den Benutzeranforderungen entspricht.
C1 noun /ˈɪmɪnəns/

imminence

Imminenz, Zustand der Nähe
Meaning
the state of being about to happen
Example
The imminence of the storm forced people to take shelter.
Die Imminenz des Sturms zwang die Menschen, Zuflucht zu suchen.
C1 adjective /ˌɪlɪˈdʒɪtɪmət/

illegitimate

illegitim
Meaning
Not authorized by law, rules, or standards; not recognized as valid.
Example
The court ruled the contract to be illegitimate.
Das Gericht entschied, dass der Vertrag illegitim war.
C1 adjective /aɪˈdɪlɪk/

idyllic

idyllisch und schön
Meaning
Like an idyll; extremely happy, peaceful, or picturesque.
Example
They enjoyed an idyllic vacation by the sea.
Sie genossen einen idyllischen Urlaub am Meer.
C1 noun /ˌɪn.səˌbɔːr.dɪˈneɪ.ʃən/

insubordination

Ungehorsam
Meaning
Defiance of authority; refusal to obey orders.
Example
The soldier was punished for insubordination during the mission.
Der Soldat wurde für Ungehorsam während der Mission bestraft.
C1 adjective ɪnˈsaɪ.sɪv

incisive

scharfsinnig
Meaning
Intelligently analytical and clear-thinking; showing clear thought and good understanding of what is important.
Example
His incisive comments revealed the core issues.
Seine scharfsinnigen Kommentare enthüllten die Kernprobleme.
C1 adjective /ɪnˈkɒmp(ə)rəbl/

incomparable

unvergleichlich
Meaning
Without an equal in quality or excellence; matchless.
Example
The view from the mountain was incomparable.
Der Ausblick vom Berg war unvergleichlich.
C1 noun /ɪnˈfɜː.mə.ti/

Infirmity

Schwäche; Krankheit; Gebrechlichkeit
Meaning
physical or mental weakness; a disease or ailment; frailty
Example
Despite his advanced age and various infirmities, he remained mentally sharp and alert.
Trotz seines fortgeschrittenen Alters und verschiedener Gebrechen blieb er geistig scharf und wachsam.
C1 adjective /ɪnˈɛlɪdʒəbəl/

Ineligible

ineligibel; nicht qualifiziert; ungeeignet
Meaning
not qualified or entitled to participate or be chosen; unsuitable
Example
Students with poor grades are ineligible for the scholarship program.
Studenten mit schlechten Noten sind für das Stipendienprogramm nicht qualifiziert.
C1 adjective /ˈɪnbɔːrn/

Inborn

angeboren; von Geburt an; inherenz
Meaning
existing from birth; natural; inherent
Example
She has an inborn talent for music.
Sie hat ein angeborenes Talent für Musik.
C1 adverb /ɪnˈvɜːrs.li/

Inversely

umgekehrt; entgegengesetzt
Meaning
in a way that is opposite or contrary; in reverse order or manner
Example
The price of goods is inversely related to their availability in the market.
Der Preis von Waren ist umgekehrt mit ihrer Verfügbarkeit auf dem Markt verbunden.
C1 adjective /ɪˈmækjələt/

immaculate

makellos
Meaning
perfectly clean, neat, or free from flaws
Example
Her room was immaculate, with everything in its place.
Ihr Zimmer war makellos, alles war an seinem Platz.
C1 noun /ɪnˈsæn.ə.ti/

Insanity

Wahnsinn; Geisteskrankheit
Meaning
the state of being seriously mentally ill; extreme foolishness or irrationality
Example
The defense lawyer argued that his client was not guilty by reason of insanity.
Der Verteidiger argumentierte, dass sein Mandant aufgrund von Wahnsinn nicht schuldig sei.
C1 noun /ɪmˈprɪzənmənt/

imprisonment

Inhaftierung
Meaning
the act of putting someone in prison; the state of being confined as punishment
Example
He faced imprisonment for violating the court order.
Er musste wegen Missachtung der Gerichtsordnung mit Inhaftierung rechnen.
C1 verb /ɪnˈterəˌɡeɪt/

interrogate

verhören
Meaning
to ask someone questions in a thorough and formal way; to question intensively
Example
The police interrogated the suspect for hours.
Die Polizei hat den Verdächtigen stundenlang verhört.
C1 noun /ˌɪnkənˈsɪstənsi/

inconsistency

Inkonsistenz
Meaning
The quality of being contradictory, irregular, or not staying the same.
Example
There is an inconsistency between his words and actions.
Es gibt eine Inkonsistenz zwischen seinen Worten und Taten.
C1 adjective /ˌɪnədˈmɪsəbl̩/

inadmissible

unzulässig
Meaning
Not allowed, especially as evidence in a court of law.
Example
The judge ruled the evidence inadmissible.
Der Richter erklärte das Beweismaterial für unzulässig.
C1 adjective /ɪnˈsɪstənt/

insistent

nachdrücklich
Meaning
demanding something firmly and refusing to accept no
Example
The child was insistent on getting a new toy.
Das Kind war nachdrücklich, ein neues Spielzeug zu bekommen.
C1 adjective ˌɪn.krəˈmen.təl

incremental

inkrementell
Meaning
Relating to or denoting an increase or addition, especially one of a series on a fixed scale; proceeding in small stages.
Example
Incremental changes ensure sustainability.
Inkrementelle Veränderungen gewährleisten Nachhaltigkeit.
C1 adjective /aɪˈreɪt/

irate

zornig
Meaning
Extremely angry.
Example
The customer became irate after waiting for hours.
Der Kunde wurde zornig, nachdem er stundenlang gewartet hatte.
C1 noun /ɪnˈkɜːrʒən/

incursion

Invasion
Meaning
A sudden attack or invasion into a place or territory.
Example
The army repelled the enemy incursion at the border.
Die Armee schlug die feindliche Invasion an der Grenze zurück.
C1 noun /ˈɪnflʌks/

influx

Zufluss
Meaning
A large arrival or flow of people or things.
Example
The city experienced an influx of tourists during the festival.
Die Stadt erlebte einen Zufluss von Touristen während des Festivals.
C1 noun /ɪnˈkɒmpɪtəns/

incompetence

Inkompetenz
Meaning
Lack of ability, skill, or effectiveness in doing something.
Example
The project failed due to the manager’s incompetence.
Das Projekt scheiterte aufgrund der Inkompetenz des Managers.
C1 noun /aɪˈtɪnərɛri/

itinerary

Reiseroute
Meaning
A planned route or schedule of a journey or trip.
Example
The travel agent gave us a detailed itinerary for our vacation.
Der Reiseveranstalter gab uns einen detaillierten Reiseplan für unseren Urlaub.
C1 verb /ɪnˈfjuːz/

infuse

infundieren
Meaning
to fill or spread through something; to instill a quality, idea, or feeling
Example
The teacher tried to infuse her students with a love for reading.
Die Lehrerin versuchte, ihren Schülern eine Liebe zum Lesen zu infundieren.
C1 verb /ɪnˈdʌkt/

induct

jemanden formell in eine Position, Organisation oder ein Amt aufnehmen
Meaning
to formally admit someone into a position, organization, or office
Example
She was inducted into the university's honor society.
Sie wurde in die Ehrenvereinigung der Universität aufgenommen.
C1 verb /ɪmˈploʊd/

implode

implodieren
Meaning
To collapse or burst inward violently.
Example
The old building imploded during the demolition.
Das alte Gebäude implodierte während der Abrissarbeiten.
C1 verb /ˈɪnfɪltreɪt/

infiltrate

infiltrieren
Meaning
to secretly enter or gain access to a place or group
Example
The spies managed to infiltrate the enemy base.
Die Spione schafften es, die feindliche Basis zu infiltrieren.
C1 noun /ˈɪnsɪdəns/

incidence

inzidenz
Meaning
the occurrence, rate, or frequency of something
Example
The incidence of road accidents has decreased this year.
Die Inzidenz von Straßenunfällen ist in diesem Jahr gesenkt worden.
C1 adjective /ˈaɪərnˌklæd/

ironclad

eiserne
Meaning
impossible to change, break, or dispute; very strong and firm
Example
The company had an ironclad contract with its suppliers.
Das Unternehmen hatte einen eisernen Vertrag mit seinen Lieferanten.
C1 adjective /ɪnˈsʌf.ər.ə.bəl/

insufferable

unerträglich
Meaning
Too extreme to bear; intolerable.
Example
The heat during the summer was insufferable.
Die Hitze im Sommer war unerträglich.
C1 adjective /ˌɪnəˈfɛnsɪv/

inoffensive

harmlos
Meaning
Not likely to offend or provoke; harmless.
Example
His inoffensive remarks kept the conversation friendly.
Seine harmlosen Bemerkungen hielten das Gespräch freundlich.
C1 verb /ɪnˈvoʊk/

invoke

anrufen
Meaning
to call upon a higher power, authority, or principle for help, support, or justification
Example
The lawyer invoked the constitution to defend his client.
Der Anwalt rief die Verfassung an, um seinen Mandanten zu verteidigen.
C1 verb /ˌɪn.trəˈspekt/

introspect

introspektieren
Meaning
To examine one's own thoughts, feelings, or mental state.
Example
He often introspects before making important decisions.
Er introspektiert oft, bevor er wichtige Entscheidungen trifft.
C1 adjective /ɪˈræʃənəl/

irrational

irrational
Meaning
not logical or reasonable; lacking clear thought
Example
His fear of the dark was completely irrational.
Seine Angst vor der Dunkelheit war völlig irrational.
C1 adjective /ˌɪndɪˈspjuːtəbəl/

Indisputable

unbestreitbar; unbestreitbar; sicher
Meaning
impossible to deny or argue against; undeniable; certain
Example
The evidence against him was indisputable.
Die Beweise gegen ihn waren unbestreitbar.
C1 adjective /ˌɪnhɒˈspɪtəbl/

inhospitable

unwirtlich
Meaning
Harsh and difficult to live in; unfriendly or unwelcoming to guests.
Example
The desert is an inhospitable environment for most plants.
Die Wüste ist ein unwirtliches Umfeld für die meisten Pflanzen.
C1 noun /ɪˈnɜː.ʃə/

Inertia

Inertie; Bewegungsmangel
Meaning
a tendency to do nothing or remain unchanged; lack of activity or movement
Example
The team's inertia prevented them from adapting to the rapidly changing market conditions.
Die Inertie des Teams verhinderte, dass es sich an die sich schnell ändernden Marktbedingungen anpasste.
C1 noun /ˌɪnkəmˈpliːtnəs/

incompleteness

Unvollständigkeit
Meaning
the state of not being complete or whole; lack of necessary parts or fullness
Example
The incompleteness of the report caused delays in the project.
Die Unvollständigkeit des Berichts verursachte Verzögerungen im Projekt.
C1 noun ɪnˌten.sɪ.fɪˈkeɪ.ʃən

intensification

Intensivierung
Meaning
The process of becoming or making something more intense or extreme.
Example
The intensification of climate change requires urgent action.
Die Intensivierung des Klimawandels erfordert dringende Maßnahmen.
C1 verb /ˈɪmprəvaɪz/

improvise

improvisieren
Meaning
To create or perform something spontaneously without preparation.
Example
The actor had to improvise his lines when he forgot the script.
Der Schauspieler musste seine Zeilen improvisieren, als er das Skript vergessen hatte.
C1 verb /ɪnˈfleɪt/

inflate

aufblasen; künstlich erhöhen
Meaning
to fill with air or gas so it expands; to increase excessively or artificially
Example
The mechanic inflated the tire to the correct pressure.
Der Mechaniker blies den Reifen auf den richtigen Druck auf.
C1 adjective /ˌɪntərˈtwaɪnd/

intertwined

Glück
Meaning
closely connected or twisted together
Example
Their lives became deeply intertwined after the accident.
Sie konnte ihr Glück nicht verbergen, als sie den Preis erhielt.
C1 noun /ˌɪntərˈmiːdiˌɛri/

intermediary

Vermittler
Meaning
A person who acts as a link between people in order to try to bring about an agreement; a mediator.
Example
The diplomat served as an intermediary between the two conflicting nations.
Der Diplomat fungierte als Vermittler zwischen den beiden konfliktierenden Nationen.
C1 adjective /ɪmˈpæsəbəl/

impassable

unpassierbar
Meaning
Impossible to travel along or over.
Example
The road became impassable after the heavy snowfall.
Die Straße wurde nach dem schweren Schneefall unpassierbar.
C1 adjective /ɪmˈpæʃənd/

impassioned

leidenschaftlich
Meaning
Filled with or showing great emotion.
Example
She gave an impassioned speech about human rights.
Sie hielt eine leidenschaftliche Rede über Menschenrechte.
C1 noun /ɪnˈsaɪtmənt/

incitement

Anstiftung
Meaning
the action of provoking unlawful or violent behavior
Example
He was arrested for incitement to riot.
Er wurde wegen Anstiftung zur Gewalt verhaftet.
C1 adjective /ɪmˈprɒmp.tjuː/

impromptu

spontan
Meaning
Done without being planned, organized, or rehearsed; spontaneous.
Example
He gave an impromptu speech at the event.
Er hielt eine spontane Rede bei der Veranstaltung.
C1 adjective /ɪnˈdʌktɪv/

inductive

induktiv
Meaning
characterized by the inference of general laws from particular instances; reasoning from specific cases to general principles
Example
The scientist used inductive reasoning to form a hypothesis.
Der Wissenschaftler verwendete induktives Denken, um eine Hypothese zu formulieren.
C1 noun /ˌɪndɪɡˈneɪʃən/

indignation

Empörung
Meaning
Strong displeasure or anger caused by something unjust, offensive, or insulting.
Example
Public indignation grew after the unfair verdict.
Öffentliche Empörung wuchs nach dem ungerechten Urteil.
C1 verb /ˈɪnstɪˌɡeɪt/

instigate

anstiften
Meaning
To bring about or initiate an action, often something negative.
Example
He was accused of instigating the riot.
Er wurde beschuldigt, den Aufstand anzustiften.
C1 noun /ɪnˈfɜːrnoʊ/

inferno

Brand
Meaning
a large, intense fire that is dangerously out of control
Example
The building turned into an inferno within minutes.
Das Gebäude verwandelte sich in ein Inferno innerhalb von Minuten.
C1 noun /ɪnˈhɛrɪtər/

inheritor

Erbe
Meaning
a person who receives money, property, or a title when someone dies
Example
She became the inheritor of her family's estate.
Sie wurde die Erbin des Familienvermögens.
C1 noun /ɪnˈdɪɡ.nə.ti/

Indignity

Indignität; Demütigung; Erniedrigung;
Meaning
treatment or circumstances that cause one to feel shame or loss of dignity; humiliation
Example
She refused to suffer the indignity of being searched without proper cause.
Sie weigerte sich, die Indignität zu ertragen, ohne einen triftigen Grund durchsucht zu werden.
C1 adjective /ɪmˈpæsɪv/

impassive

passiv
Meaning
Not showing or feeling emotion; expressionless.
Example
Despite the shocking news, she remained impassive.
Trotz der schockierenden Nachrichten blieb sie passiv.
C1 adjective /ɪmˈpɛtʃ.u.əs/

impetuous

impulsiv
Meaning
Acting or done quickly and without thought or care; impulsive.
Example
His impetuous decision led to unexpected consequences.
Seine impulsive Entscheidung führte zu unerwarteten Konsequenzen.
C1 adjective /ɪmˈpɜːrtɪnənt/

impertinent

unverschämt
Meaning
rude and showing a lack of respect
Example
It was impertinent of him to question the manager's decision.
Es war unverschämt von ihm, die Entscheidung des Managers zu hinterfragen.
C1 adjective /ˌɪnɪkˈsplɪkəbl/

inexplicable

unverständlich
Meaning
Impossible to explain or understand.
Example
The sudden disappearance of the file was inexplicable.
Das plötzliche Verschwinden der Datei war unverständlich.
C1 noun ˌɪndɪˈspensəbl səˈpɔːrt

indispensable support

unverzichtbare Unterstützung
Meaning
Essential assistance that cannot be done without; absolutely necessary help.
Example
Volunteers provide indispensable support to communities.
Freiwillige leisten unverzichtbare Unterstützung für Gemeinschaften.
C1 noun /ɪmˈpɜːrtɪnəns/

impertinence

Unverschämtheit
Meaning
lack of respect; rudeness
Example
The teacher was shocked by the student's impertinence.
Der Lehrer war schockiert über die Unverschämtheit des Schülers.
C1 noun /ˌɪməˈrælɪti/

immorality

Unmoral
Meaning
the quality of being immoral; behavior that violates accepted moral standards
Example
The community condemned the immorality of the corrupt officials.
Die Gemeinschaft verurteilte die Unmoral der korrupten Beamten.
C1 adjective /ɪnˈedəbəl/

Inedible

ungenießbar
Meaning
not suitable or safe for eating; not edible
Example
The mushrooms were poisonous and completely inedible.
Die Pilze waren giftig und völlig ungenießbar.
C1 adjective /ɪnˈflæməbəl/

Inflammable

entzündlich; brennbar
Meaning
easily set on fire; flammable; combustible
Example
The inflammable material caught fire quickly.
Das entzündliche Material brannte schnell.
C1 adjective /ɪmˈpjʊər/

Impure

unrein
Meaning
contaminated; not clean; mixed with foreign substances
Example
The impure water caused health problems in the village.
Das unreine Wasser verursachte Gesundheitsprobleme im Dorf.
C1 verb /ɪnˈtɒksɪkeɪt/

intoxicate

Glück
Meaning
to make someone lose control of their faculties or behavior due to alcohol or drugs
Example
The strong drink quickly intoxicated him.
Sie konnte ihr Glück nicht verbergen, als sie den Preis erhielt.
C1 noun /ˈɪn.tə.mə.si/

Intimacy

Intimität; Nähe
Meaning
close familiarity or friendship; closeness; a private cozy atmosphere
Example
The couple valued the emotional intimacy they shared more than material possessions.
Das Paar schätzte die emotionale Intimität, die sie teilten, mehr als materiellen Besitz.
C1 adjective /ˌɪnkənˈsɪdərət/

inconsiderate

rücksichtslos
Meaning
Thoughtless; showing a lack of concern for others.
Example
It was inconsiderate of him to play loud music late at night.
Es war rücksichtslos von ihm, nachts laute Musik zu spielen.
C1 noun /ˌɪnˈdɪsəplɪn/

indiscipline

Undiszipliniertheit
Meaning
lack of discipline or self-control; failure to obey rules or maintain order
Example
Indiscipline among the students disrupted the learning environment.
Die Undiszipliniertheit der Schüler störte die Lernumgebung.
C1 verb ɪˈnɔː.ɡjə.reɪ.tɪd

inaugurated

eingeweiht
Meaning
Begin or introduce (a system, policy, or period) formally.
Example
The organization was inaugurated officially.
Die Organisation wurde offiziell eingeweiht.
C1 noun /ˌɪntərˌɒpərəˈbɪləti/

interoperability

Interoperabilität
Meaning
The ability of computer systems or software to exchange and make use of information.
Example
The interoperability of different software systems ensures seamless workflow.
Die Interoperabilität verschiedener Softwaresysteme gewährleistet einen nahtlosen Arbeitsablauf.
C1 adjective /ɪnˈdɪɡnənt/

indignant

empört
Meaning
Feeling or showing anger at something considered unfair or unjust.
Example
She was indignant when accused of cheating.
Sie war empört, als sie des Schummelns beschuldigt wurde.
C1 verb /ɪnˈhɪbɪt/

inhibit

hemmen
Meaning
to prevent or restrain someone or something from acting freely; to hinder
Example
Fear can inhibit personal growth.
Angst kann das persönliche Wachstum hemmen.
C1 adverb /ˌɪn.dɪˈskrɪm.ɪ.nət.li/

Indiscriminately

indiskriminierend
Meaning
without making careful distinctions; randomly; without discrimination
Example
The company fired employees indiscriminately without considering their performance.
Das Unternehmen entließ die Mitarbeiter ohne Rücksicht auf ihre Leistung.
C1 adjective /ɪˈmjuː.tə.bəl/

immutable

unveränderlich
Meaning
Unchangeable, permanent, or fixed
Example
The laws of physics are considered immutable.
Die Gesetze der Physik gelten als unveränderlich.
C1 verb ɪˈnɪʃɪeɪtɪd

initiated

initiiert
Meaning
Caused a process or action to begin; started something.
Example
The project was initiated to enhance marine biodiversity.
Das Projekt wurde initiiert, um die marine Biodiversität zu verbessern.
C1 noun /ɪnˈfjuːʒən/

infusion

Infusion
Meaning
the act of introducing something into another; a drink made by steeping leaves or herbs in liquid
Example
She prepared a calming infusion of chamomile tea.
Sie bereitete eine beruhigende Infusion aus Kamillentee zu.
C1 adjective ɪnɪɡˈzɔːstɪbəl

inexhaustible

unerschöpflich
Meaning
Unable to be used up or worn out; limitless.
Example
His inexhaustible energy allowed him to work tirelessly on his projects.
Seine unerschöpfliche Energie ermöglichte es ihm, unermüdlich an seinen Projekten zu arbeiten.
C1 verb /ɪnˈsɪnjueɪt/

insinuate

insinuieren
Meaning
To suggest or hint something indirectly and often unpleasantly.
Example
He insinuated that she had lied about her qualifications.
Er insinuierte, dass sie über ihre Qualifikationen gelogen hatte.
C1 adjective /ˌɪnækˈsɛsəbl/

inaccessible

unzugänglich
Meaning
unable to be reached, entered, or understood
Example
The remote village is almost inaccessible during the rainy season.
Das abgelegene Dorf ist während der Regenzeit fast unzugänglich.
C1 adjective /ˌɪndɪˈskrɪmɪnət/

indiscriminate

willkürlich
Meaning
Done without careful judgment; random or haphazard.
Example
The indiscriminate use of pesticides harms the environment.
Der willkürliche Einsatz von Pestiziden schadet der Umwelt.
C1 noun /ɪnˈækjʊrəsi/

inaccuracy

Ungenauigkeit
Meaning
lack of accuracy or precision; an incorrect or wrong detail
Example
The report contained several factual inaccuracies.
Der Bericht enthielt mehrere Ungenauigkeiten.
C1 noun ˌɪnsjʊˈleɪʃən

insulation

Isolierung
Meaning
Material used to prevent heat, sound, or electricity from being transmitted from one area to another.
Example
Insulation of food storage areas can prevent pests from entering.
Die Isolierung von Lebensmittel-Lagerbereichen kann verhindern, dass Schädlinge eindringen.
C1 noun /ɪnˈsɜːrdʒəns/

insurgence

Aufstand
Meaning
An act of rebellion or uprising against authority.
Example
The government struggled to contain the growing insurgence.
Die Regierung hatte Schwierigkeiten, den wachsenden Aufstand zu bekämpfen.
C1 noun /ɪnˈtruː.ʒən/

intrusion

unbefugtes Eindringen
Meaning
Unauthorized entry into a system or place without permission
Example
The company detected an intrusion in its server.
Das Unternehmen hat eine Intrusion in seinem Server erkannt.
C1 noun ɪˌræʃ.ənˈæl.ɪ.ti

irrationality

Irrationalität, Unvernunft, Unlogik
Meaning
The quality of being illogical or unreasonable; lack of rational thought.
Example
His decision was driven by complete irrationality.
Seine Entscheidung war von völliger Irrationalität getrieben.
C1 adjective /ˌɪn.səbˈstæn.ʃəl/

insubstantial

unwesentlich
Meaning
Lacking strength, substance, or solidity.
Example
The evidence provided was insubstantial and unconvincing.
Die bereitgestellten Beweise waren unwesentlich und wenig überzeugend.
C1 adjective /ˌɪməˈtɪəriəl/

immaterial

unwichtig
Meaning
Not important or relevant; lacking physical substance.
Example
The judge ruled that the argument was immaterial to the case.
Der Richter entschied, dass das Argument für den Fall unerheblich war.
C1 noun /ˌɪn.dɪˈsɪʒ.ən/

Indecision

Unentschlossenheit; Zweifel; Zögern
Meaning
the inability to make decisions quickly; uncertainty about what to do
Example
Her indecision about which job offer to accept caused her to miss both opportunities.
Ihre Unentschlossenheit, welches Jobangebot sie annehmen sollte, führte dazu, dass sie beide Gelegenheiten verpasste.
C1 adverb, adjective /ˌɪnkɑːɡˈniːtoʊ/

incognito

inkognito
Meaning
In disguise or with one's identity concealed.
Example
The celebrity traveled incognito to avoid the paparazzi.
Der Promi reiste inkognito, um den Paparazzi zu entkommen.
C1 adjective /ˈɪntrɪkət/

intricate

komplex
Meaning
very detailed, complex, and difficult to understand
Example
The artist created an intricate pattern on the wall.
Der Künstler hat ein komplexes Muster an die Wand gemalt.
C1 adjective /ˈɪmpjəd(ə)nt/

impudent

frech, unverschämt
Meaning
not showing due respect for another person; rude
Example
The impudent child talked back to the teacher.
Das freche Kind antwortete dem Lehrer.
C1 verb /ɪnˈsaɪt/

incite

anstacheln
Meaning
to provoke; to stir up
Example
His speech incited the crowd to violence.
Seine Rede hat die Menge zu Gewalt angestachelt.
C1 adjective /ɪnˈstrʌktɪv/

instructive

instruktiv
Meaning
useful and informative; providing knowledge or instruction
Example
The lecture was highly instructive and engaging.
Der Vortrag war sehr lehrreich und fesselnd.
C1 noun ˌɪn.tuˈɪʃ.ən

intuition

Intuition
Meaning
The ability to understand something immediately, without the need for conscious reasoning.
Example
Her intuition told her something was wrong.
Ihre Intuition sagte ihr, dass etwas nicht stimmte.
C1 adjective /ˌɪntərˈtʃeɪndʒəbl/

interchangeable

austauschbar
Meaning
able to be exchanged with each other without difference or loss of function
Example
These machine parts are interchangeable, so they can be replaced easily.
Diese Maschinenteile sind austauschbar, so dass sie einfach ersetzt werden können.
C1 adjective /ɪnˈvɑːlənˌtɛri/

involuntary

unfreiwillig
Meaning
done without will or conscious control
Example
He gave an involuntary shiver when he heard the loud noise.
Er bekam einen unwillkürlichen Schauer, als er das laute Geräusch hörte.
C1 adverb ɪnˈtrɪn.zɪ.kli

intrinsically

intrinsisch
Meaning
In a way that is naturally or inherently part of something's essential nature.
Example
Some people are intrinsically motivated to learn.
Einige Menschen sind intrinsisch motiviert zu lernen.
C1 adjective /ɪnˈtrɛpɪd/

intrepid

unerschrocken
Meaning
fearless and adventurous, often used humorously
Example
The intrepid traveler explored the jungle alone.
Der unerschrockene Reisende erkundete den Dschungel alleine.
C1 noun ˌɪndɪˈspensəbl̩ ˈkɒmpɪtənsi

indispensable competency

unverzichtbare Kompetenz
Meaning
Essential skill or ability that cannot be done without; a crucial capability that is absolutely necessary.
Example
Digital literacy is an indispensable competency in the 21st century.
Digitale Kompetenz ist eine unverzichtbare Kompetenz im 21. Jahrhundert.
C1 noun /ˈɪn.fən.tri/

Infantry

infanterie
Meaning
soldiers marching or fighting on foot; foot soldiers collectively
Example
The infantry advanced across the battlefield on foot.
Die Infanterie marschierte zu Fuß über das Schlachtfeld.
C1 adjective ˌɪm.pəˈsɛp.tɪ.bəl

imperceptible

unmerklich
Meaning
So subtle or gradual that it is difficult to notice or perceive
Example
The changes in his behavior were imperceptible at first.
Die Veränderungen in seinem Verhalten waren anfangs unmerklich.
C1 adjective /ˈɪɡ.ni.əs/

igneous

magmatisch
Meaning
Formed through the cooling and solidification of magma or lava.
Example
Granite is an igneous rock commonly used in construction.
Granit ist ein magmatisches Gestein, das häufig im Bauwesen verwendet wird.
C1 adjective /ɪnˈsteɪbəl/

instable

instabil
Meaning
not stable; liable to change, collapse, or fail; lacking firmness or reliability
Example
The instable political situation worried foreign investors.
Die instabile politische Lage beunruhigte ausländische Investoren.
C1 adjective /ɪˈrɛvərənt/

irreverent

respektlos
Meaning
showing a lack of respect for people or things that are usually respected
Example
The comedian’s irreverent jokes offended some of the audience.
Die respektlosen Witze des Komikers haben einige Zuschauer beleidigt.
C1 adjective /ɪnˈdʌstriəs/

industrious

fleißig
Meaning
Hardworking and diligent in one's duties.
Example
She is an industrious student who always completes her assignments on time.
Sie ist eine fleißige Studentin, die immer ihre Aufgaben rechtzeitig erledigt.
C1 verb /ɪnˈtruːd/

intrude

einmischen
Meaning
To enter a place or situation where one is not wanted or not invited.
Example
He felt embarrassed to intrude on their private conversation.
Er fühlte sich peinlich berührt, in ihr privates Gespräch einzutreten.
C1 noun /ɪnˈdem.nə.ti/

Indemnity

Entschädigung
Meaning
security or protection against a loss or other financial burden; compensation for damage or loss
Example
The insurance company provided full indemnity for the damages caused by the flood.
Die Versicherungsgesellschaft stellte vollständige Entschädigung für die durch die Flut verursachten Schäden bereit.
C1 noun /ˌɪndɪˈdʒɛstʃən/

indigestion

Verdauungsstörung
Meaning
Discomfort or pain in the stomach associated with difficulty in digesting food.
Example
He avoided spicy food because it often gave him indigestion.
Er vermied scharfes Essen, weil es ihm oft Verdauungsstörungen verursachte.
C1 noun (plural) /ˈɪndɪˌsiːz/

indices

Indizes
Meaning
plural form of index; statistical measures or reference points used for comparison
Example
Stock market indices fell sharply after the announcement.
Die Indizes des Aktienmarkts fielen nach der Bekanntgabe stark.
C1 verb /ˈɪnsjuleɪt/

insulate

isolieren
Meaning
To protect something by covering it, especially to prevent heat, sound, or electricity from escaping or entering.
Example
The house was insulated to reduce heating costs.
Das Haus wurde isoliert, um die Heizkosten zu senken.
C1 adjective /ɪˈlɒdʒ.ɪ.kəl/

Illogical

Illogisch
Meaning
not reasonable or sensible; lacking logic
Example
It would be illogical to go swimming in such cold weather.
Es wäre illogisch, bei solch kaltem Wetter schwimmen zu gehen.
C1 noun /ɪnˈsek.tɪ.saɪd/

Insecticide

Insektizid
Meaning
a substance used for killing insects; a chemical pesticide that targets insects
Example
The farmer sprayed insecticide on his crops to protect them from harmful bugs.
Der Bauer sprühte Insektizid auf seine Ernte, um sie vor schädlichen Insekten zu schützen.
C1 adjective /ˌɪnˌkɒnsɪˈkwɛnʃəl/

inconsequential

unbedeutend
Meaning
Not important or significant; too small to matter.
Example
The mistake was minor and inconsequential.
Der Fehler war geringfügig und unbedeutend.
C1 noun /ˈɪmɪdʒəri/

imagery

Bildsprache
Meaning
visually descriptive or figurative language, especially in a literary work
Example
The poet's use of imagery brought the scene to life.
Der Einsatz von Bildsprache des Dichters erweckte die Szene zum Leben.
C1 noun /ɪmˌpɒsəˈbɪlɪti/

impossibility

Unmöglichkeit
Meaning
the state or fact of being impossible; something that cannot be done or achieved
Example
Finishing the project in one day was an impossibility.
Das Projekt an einem Tag zu beenden war eine Unmöglichkeit.
C1 adjective /ɪˈrɛpərəbəl/

Irreparable

irreparabel
Meaning
impossible to repair or fix; permanent damage that cannot be undone
Example
The accident caused irreparable damage to his spine.
Der Unfall verursachte irreparable Schäden an seiner Wirbelsäule.
C1 adjective, noun /ˈɪnvəlɪd/ (adjective), /ɪnˈvælɪd/ (noun)

invalid

ungültig
Meaning
Not valid; having no force or effect. Also refers to a person too weak or ill to care for themselves.
Example
The court declared the contract invalid.
Das Gericht erklärte den Vertrag für ungültig.