impact
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B1 noun ˈɪmpækt

impact

影響
Meaning
A strong effect or influence; the action of one object coming forcibly into contact with another.
Example
The decision had great impact.
その決定は大きな影響を与えた。
A2 pronoun /ɪtˈsɛlf/

itself

それ自身
Meaning
Used to emphasize the thing just mentioned; by its own power or effort.
Example
The cat cleaned itself after eating.
猫は食べた後、自分で自分をきれいにした。
C1 noun ˈɪm.pɪ.təs

impetus

推進力
Meaning
The force or motivation that drives something forward; momentum.
Example
The new policy provided an impetus for economic growth.
新しい政策は経済成長のための推進力を提供しました。
C1 adjective /ˌɪnsɪˈdɛntəl/

incidental

付随的
Meaning
happening as a minor part or in connection with something else
Example
Incidental expenses like snacks and tips were included in the bill.
スナックやチップのような付随的な費用は請求書に含まれていました。
B1 noun /ˈɪnstrəmənt/

instrument

楽器
Meaning
A tool or device used for a particular purpose, especially for scientific or musical work.
Example
The doctor used a special instrument during the surgery.
医師は手術中に特別な楽器を使用しました。
C1 adjective /ɪˈlʌstriəs/

illustrious

著名
Meaning
Well known, respected, and admired for past achievements.
Example
She had an illustrious career in medicine.
彼女は医学の分野で著名なキャリアを持っていた。
C2 adjective /ɪmˈpɒndərəbl̩/

imponderable

計り知れない
Meaning
Something difficult or impossible to estimate, assess, or understand
Example
The outcome of the election depends on many imponderable factors.
選挙の結果は、多くの計り知れない要因に依存しています。
C2 adjective /ˈɪn.dɪ.dʒənt/

indigent

困窮
Meaning
lacking the necessities of life due to poverty; very poor
Example
The hospital offers free care to indigent patients.
病院は困窮した患者に無料でケアを提供しています。
C2 noun /ɪˈmɒdəsti/

immodesty

不謹慎
Meaning
lack of modesty or decency; behavior or attitude that is overly bold or improper
Example
The article was criticized for its tone of immodesty.
その記事は不謹慎な語調で批判された。
C2 verb /ˌɪmpɔːrˈtuːnd/

importuned

しつこく頼む
Meaning
asked someone persistently and pressingly for something
Example
She importuned her boss for a raise until he finally gave in.
彼女は昇給を求めて上司にしつこく頼んだ、彼がとうとう折れたまで。
B2 adverb /ɪmˈpɔːtəntli/

importantly

重要な方法で
Meaning
in a way that is of great significance or value
Example
Importantly, the report highlights the need for immediate action.
重要な方法で、報告書は即時の行動の必要性を強調しました。
C2 adjective /ˌɪnsəˈpɔːrtəbl̩/

insupportable

耐えられない
Meaning
Too extreme or difficult to be endured.
Example
The heat was insupportable during the long journey.
長い旅の間、暑さは耐えられなかった。
B2 noun, verb /ˌɪnkənˈviːniəns/

inconvenience

不便
Meaning
trouble or difficulty caused to someone; to cause trouble or difficulty to someone
Example
We apologize for any inconvenience caused by the delay.
遅延によって生じた不便についてお詫びします。
C2 adjective /ɪnˈskruːtəbl̩/

inscrutable

幸福
Meaning
impossible to understand or interpret
Example
His inscrutable expression made it hard to know what he was thinking.
彼女は賞を受け取ったとき、幸せを隠すことができませんでした。
C1 adjective, noun /ɪnˈdɪkətɪv/

indicative

指示的
Meaning
Serving as a sign or expression of something; in grammar, a mood used to make factual statements.
Example
His tone was indicative of his frustration.
彼のトーンは彼のフラストレーションを示していた。
C1 verb /ɪnˈdʌkt/

induct

Meaning
to formally admit someone into a position, organization, or office
Example
She was inducted into the university's honor society.
C2 adjective /ɪnˈsɛndiˌɛri/

incendiary

扇動的な / 挑発的な
Meaning
designed to cause fires or stir up conflict
Example
The politician’s incendiary remarks angered the crowd.
政治家の挑発的な発言が群衆を怒らせた。
C2 noun /ˌaɪ.diˈeɪ.ʃən/

ideation

アイデア創出
Meaning
The process of forming and developing new ideas or concepts through creative thinking and brainstorming.
Example
The team engaged in ideation sessions to generate new product ideas.
チームは新製品のアイデアを生み出すためにアイデーションセッションに取り組んだ。
C2 adjective /ɪmˈplækəbl/

implacable

容赦しない
Meaning
unable to be appeased, calmed, or pacified
Example
The soldiers faced an implacable enemy who refused to surrender.
兵士たちは降伏を拒否した容赦しない敵に直面した。
B1 noun /ˌɪntərˈækʃən/

interaction

相互作用
Meaning
The process of people or things acting upon or influencing each other.
Example
The teacher encouraged more interaction between students.
教師は生徒間のさらなるインタラクションを促進しました。
C1 noun /ˌɪntɪˈmeɪʃən/

intimation

示唆
Meaning
A subtle or indirect hint or suggestion.
Example
She gave no intimation of her plans.
彼女は自分の計画について何の示唆も与えなかった。
B2 adjective /ɪˈlɪt.ər.ət/

Illiterate

識字障害者; 読み書きができない; 無知
Meaning
unable to read or write; lacking education
Example
The program aims to help illiterate adults learn to read and write.
このプログラムは、識字率の低い成人が読み書きを学ぶ手助けをすることを目的としています。
C2 noun /ɪmˈpɒs.tʃər/

Imposture

偽装; 詐欺; 虚偽
Meaning
the practice of deceiving others by pretending to be someone else; fraudulent deception
Example
The elaborate imposture lasted for months before investigators uncovered the truth.
その精巧な詐欺は数ヶ月続き、調査員が真実を明らかにするまで続いた。
C1 noun ɪnˌɛv.ɪ.təˈbɪl.ɪ.ti

inevitability

避けられない運命
Meaning
The quality of being certain to happen and impossible to avoid or prevent.
Example
The inevitability of change is a part of life.
変化の避けられないことは人生の一部です。
C1 adjective /ɪˈmuː.və.bəl/

immovable

動かせない
Meaning
Not able to be moved; fixed in position.
Example
Immovable barriers prevent change.
動かせない障害物が変化を妨げる。
C1 adjective /ˌaɪ.di.əˈlɒdʒ.ɪ.kəl/

ideological

イデオロギー的
Meaning
Relating to or based on a system of ideas or beliefs.
Example
The two parties are divided by deep ideological differences.
二つの党は深いイデオロギー的な違いによって分裂している。
C1 noun ˌɪn.tuˈɪʃ.ən

intuition

直感
Meaning
The ability to understand something immediately, without the need for conscious reasoning.
Example
Her intuition told her something was wrong.
彼女の直感は何かが間違っていると言った。
C1 verb /ɪˈluːmɪneɪt/

illuminate

照らす
Meaning
To light up or make something clearer.
Example
Streetlights illuminate the road at night.
街路灯が夜に道路を照らします。
C2 noun /ˌɪnkənˈɡruːəti/

incongruity

不一致
Meaning
The state of being inconsistent or out of place.
Example
The incongruity of his cheerful mood during the funeral shocked everyone.
葬式の最中に彼の陽気な気分の不一致は、皆を驚かせました。
C2 adjective /ɪnˈtɛmpərət/

intemperate

不節制な
Meaning
Lacking self-control; immoderate, especially in indulgence.
Example
The politician's intemperate remarks caused controversy.
政治家の不節制な発言は論争を引き起こした。
C2 verb /ˌɪnkəˈpæsɪteɪt/

incapacitate

無力化する
Meaning
to deprive someone or something of the ability or strength to function
Example
The severe injury incapacitated the player for the rest of the season.
その重傷はプレーヤーをシーズンの残りの期間無力化させた。
C2 adjective /ɪˈmɒdərət/

immoderate

過度な
Meaning
excessive; beyond reasonable limits
Example
He has an immoderate love for sweets.
彼はお菓子に対して過度の愛情を持っています。
C2 noun /ɪmˈpjuːɪsəns/

impuissance

無力, 無能
Meaning
inability to take effective action; helplessness
Example
The government’s impuissance in the face of crisis frustrated the people.
危機の前で政府の無力さが人々を失望させた。
C1 adverb /ɪnˈdɛfɪnətli/

indefinitely

無期限で
Meaning
for an unlimited or unspecified period of time
Example
The project has been postponed indefinitely.
プロジェクトは無期限で延期されました。
B2 adjective /ɪnˈsɛnsətɪv/

insensitive

無神経な
Meaning
Showing or feeling no concern for others' feelings.
Example
His insensitive comment hurt her deeply.
彼の無神経なコメントは彼女を深く傷つけました。
B2 adjective /ɪˈrɛləvənt/

Irrelevant

無関係な
Meaning
not connected with or relevant to something; having no bearing on the matter
Example
Your past mistakes are irrelevant to this discussion.
あなたの過去の過ちはこの議論には無関係です。
B2 noun ɪnˈdʒʌstɪs

injustice

不正義
Meaning
Lack of fairness or justice; the practice of being unjust or unfair.
Example
The story portrays the injustices faced by the common people.
物語は一般の人々が直面する不正義を描いています。
C2 noun /ˈaɪdɪl/

idyll

田園詩的なシーン
Meaning
An extremely happy, peaceful, or picturesque episode or scene, often idealized.
Example
Their honeymoon was an idyll on a tropical island.
彼らのハネムーンは熱帯の島での田園詩的なシーンでした。
C2 noun /ɪnˈtɜːrstɪs/

interstice

隙間
Meaning
a small space that lies between things
Example
Light filtered through the narrow interstices of the wall.
光は壁の狭い隙間を通して漏れた。
C2 noun /ˈɪnsələns/

insolence

無礼
Meaning
rude or disrespectful behavior
Example
The teacher was shocked by the student's insolence.
教師は学生の無礼に驚きました。
B2 adjective /ˌɪn.trəˈdʌk.tər.i/

introductory

導入の
Meaning
Serving as an introduction; preliminary or preparatory.
Example
The professor gave an introductory lecture on economics.
教授は経済学についての導入の講義を行いました。
B1 verb /ˌɪntərˈækt/

interact

交流する
Meaning
to communicate or work together with someone or something
Example
Students interact with teachers during class discussions.
学生は授業のディスカッション中に教師と交流します。
C1 adjective ˌɪn.tə.dʒen.əˈreɪ.ʃən.əl

intergenerational

世代間、異なる世代間で発生する
Meaning
Existing or occurring between different generations of a family.
Example
Intergenerational wisdom ensures cultural continuity.
インタージェネレーショナルな知恵は文化的継続性を確保する。
C1 adjective /ɪˈmjuː.tə.bəl/

immutable

不変の
Meaning
Unchangeable, permanent, or fixed
Example
The laws of physics are considered immutable.
物理法則は不変と見なされます。
C2 noun /ɪkˈsɔːr.ə/

Ixora

イクソラ
Meaning
a tropical flowering shrub with clusters of small bright red, orange, or yellow flowers
Example
The bright red ixora bushes lined the pathway to the tropical garden.
明るい赤いイクソラの低木が熱帯庭園への小道を囲んでいました。
C1 adjective /ˈɪnbɔːrn/

Inborn

生まれつきの; 生来の; 内在的な
Meaning
existing from birth; natural; inherent
Example
She has an inborn talent for music.
彼女は音楽のための生まれつきの才能を持っています。
C2 adjective /ˌɪrɪˈtriːvəbl/

irretrievable

回復不可能
Meaning
impossible to recover or regain
Example
The documents were lost in an irretrievable way after the fire.
火事の後、文書は回復不可能な方法で失われました。
C2 adjective /ˈɪndələnt/

indolent

怠惰
Meaning
Wanting to avoid activity or exertion; lazy.
Example
The indolent cat slept in the sun all afternoon.
怠惰な猫は午後ずっと太陽の下で寝ていました。
B1 adjective ɪnˈdʌs.tri.əl

industrial

工業的な
Meaning
Relating to or characterized by industry.
Example
Industrial sectors boost exports.
工業部門は輸出を促進する。
B2 adjective /ˈɪn.tɪ.mət/

Intimate

親密な; 個人的な; 詳細な知識
Meaning
close in friendship; private and personal; detailed knowledge
Example
They have an intimate friendship that has lasted for decades.
彼らは何十年にもわたる親密な友情を持っています。
C2 noun /ˈɪnˌɡreɪt/

ingrate

Meaning
An ungrateful person; someone who shows no appreciation.
Example
He worked hard for his friend, but the ingrate never thanked him.
C2 verb /ˈɪŋkʌlpeɪt/

inculpate

非難する
Meaning
To blame or accuse someone of wrongdoing.
Example
The evidence seemed to inculpate the suspect in the crime.
証拠は容疑者を犯行に巻き込んでいるように見えた。
C1 adjective /ɪnˈkɒmp(ə)rəbl/

incomparable

比類のない
Meaning
Without an equal in quality or excellence; matchless.
Example
The view from the mountain was incomparable.
山からの景色は比類のないものでした。
B1 verb /aɪˈdentɪfaɪ/

identify

識別する
Meaning
to recognize; to establish who someone is
Example
Can you identify the suspect?
容疑者を特定できますか?
C1 noun /ˈɪm.pæs/

impasse

行き詰まり
Meaning
A situation where no progress is possible.
Example
The negotiations reached an impasse, delaying the agreement.
交渉は行き詰まり、合意が遅れた。
C1 adjective /ˌɪndɪˈstrʌktəbl/

indestructible

壊れない
Meaning
Impossible to destroy or break.
Example
The superhero's shield was said to be indestructible.
スーパーヒーローの盾は壊れないと言われていました。
C2 noun /ɪˈnɪkwɪti/

iniquity

不正
Meaning
Immoral or grossly unfair behavior.
Example
The dictator's regime was marked by corruption and iniquity.
独裁者の政権は腐敗と不正で特徴づけられていました。
C2 adjective /ɪˈlɪmɪtəbl/

illimitable

無限
Meaning
Without limits or bounds.
Example
The universe is often described as illimitable.
宇宙はしばしば無限であると説明されます。
C1 adjective /ɪnˈdʌldʒənt/

indulgent

寛容な
Meaning
Having a tendency to be overly generous or lenient with someone.
Example
The indulgent mother allowed her child to stay up late.
寛容な母は子供を遅くまで起きていることを許しました。
C2 noun /ˌɪmprəˈpraɪəti/

impropriety

不正行為
Meaning
Failure to observe standards of honesty or modesty; improper behavior.
Example
The politician was accused of financial impropriety.
その政治家は財政的不正行為で告発されました。
C2 adjective /ɪnˈdjuːbɪtəbl/

indubitable

疑う余地がない
Meaning
Impossible to doubt; unquestionable.
Example
It is indubitable that hard work leads to success.
努力すれば成功に繋がることは疑う余地がない。
C2 adjective /ɪnˈsɪpiənt/

incipient

初期の
Meaning
in an initial stage; beginning to develop
Example
The incipient storm made the sky turn dark and heavy.
初期の嵐が空を暗く重くさせた。
B2 noun /ɪsˈlɑːm/

islam

イスラム教
Meaning
the religion founded by the Prophet Muhammad, based on belief in one God (Allah)
Example
Islam emphasizes peace, justice, and compassion.
イスラム教は平和、正義、そして慈悲を強調します。
C1 adjective /ɪnˈflæməˌtɔːri/

inflammatory

幸せ
Meaning
causing inflammation in the body; arousing anger, hostility, or strong emotion
Example
His inflammatory speech triggered protests across the city.
彼女は賞を受け取ったとき、幸せそうな表情を隠せなかった。
C1 adjective /ɪnˈdefɪnət/

Indefinite

不確定な
Meaning
not clearly defined; uncertain; vague; unlimited in time
Example
The meeting has been postponed for an indefinite period.
会議は不確定な期間に延期されました。
A1 noun /aɪs/

Ice

Meaning
water that has frozen and become solid
Example
The ice in my drink melted quickly in the hot weather.
私の飲み物の氷は暑い天気で素早く溶けました。
C1 adjective /ɪnˈdʒʊəriəs/

injurious

有害な
Meaning
Causing or likely to cause harm or damage.
Example
Smoking is injurious to health.
喫煙は健康に有害です。
C2 conjunction /ˌɪnəzˈmʌtʃ æz/

inasmuch-as

なぜなら
Meaning
Because; since.
Example
He cannot attend, inasmuch as he is unwell.
彼は出席できません、なぜなら彼は病気だからです。
C2 verb /ɪnˈveɪ/

inveigh

激しく批判する
Meaning
To speak or write about something with great hostility and criticism.
Example
He inveighed against the corruption in government.
彼は政府の腐敗に対して激しく批判した。
B2 verb /ˈɪnəveɪt/

innovate

革新
Meaning
To introduce new methods, ideas, or products.
Example
The company must innovate to stay ahead of its competitors.
その企業は競争相手を追い越すために革新を続けなければならない。
C1 adjective /ɪnˈvɑːlənˌtɛri/

involuntary

不随意
Meaning
done without will or conscious control
Example
He gave an involuntary shiver when he heard the loud noise.
彼は大きな音を聞いたとき、不随意に震えた。
C1 verb /ɪnˈskraɪb/

inscribe

刻む
Meaning
to write or carve words or symbols on a surface
Example
They inscribed her name on the trophy.
彼らはトロフィーに彼女の名前を刻みました。
C2 adjective /ɪnˈsɛptɪv/

inceptive

初期の
Meaning
Relating to or marking the beginning or initial stage of something.
Example
The inceptive phase of the project was marked by enthusiastic planning.
プロジェクトの開始段階は熱心な計画で特徴づけられました。
B2 adjective /ɪˈmens/

Immense

巨大な; 膨大な; 非常に大きい
Meaning
extremely large or great; huge
Example
The immense mountain range stretched across the horizon.
その巨大な山脈は地平線を越えて広がっていました。
C2 noun /ɪnˈtɒksɪkənt/

intoxicant

酔わせる物質
Meaning
a substance, especially alcohol or a drug, that causes intoxication
Example
Alcohol is the most commonly used intoxicant in many cultures.
アルコールは多くの文化で最も一般的に使用される酔わせる物質です。
C1 adjective /ˌɪn.səˈbɔːr.dɪ.nət/

insubordinate

命令不服従
Meaning
Defiant of authority; disobedient to orders.
Example
The insubordinate employee refused to follow the manager's instructions.
命令不服従の従業員は、マネージャーの指示に従うことを拒否した。
C2 verb ɪmˈbaɪb

imbibe

吸収する, 同化する, 飲む
Meaning
Absorb or assimilate ideas or knowledge. To drink or take in.
Example
He tried to imbibe the wisdom from his mentor.
彼は師匠から知恵を吸収しようとした。
C2 noun /ˌɪmbəˈsɪləti/

imbecility

愚かさ
Meaning
Extreme foolishness, stupidity, or weakness of mind.
Example
The plan was abandoned due to its sheer imbecility.
その計画はその愚かさから放棄されました。
A1 noun /ˈaɪs kriːm/

Ice-cream

アイスクリーム
Meaning
a frozen sweet dessert made from dairy products, usually served cold
Example
Children love to eat ice-cream on hot summer days.
子供たちは暑い夏の日にアイスクリームを食べるのが好きです。
C1 adjective /ˌɪn.səbˈstæn.ʃəl/

insubstantial

不十分な
Meaning
Lacking strength, substance, or solidity.
Example
The evidence provided was insubstantial and unconvincing.
提供された証拠は不十分で説得力がなかった。
C1 noun ˌɪm.pʌlˈsɪv.ɪ.ti

impulsivity

衝動性
Meaning
The tendency to act quickly and without thought or care; lack of self-control.
Example
His impulsivity led him to make reckless choices.
彼の衝動性は、無謀な選択をさせた。
C2 adjective /ɪnˈɡlɔːriəs/

inglorious

不名誉な
Meaning
Causing shame or disgrace; not bringing honor or glory.
Example
The army suffered an inglorious defeat.
軍隊は不名誉な敗北を喫した。
A1 pronoun /aɪ/

i

Meaning
used by a speaker to refer to himself or herself
Example
I am learning English every day.
私は毎日英語を学んでいます。
C1 verb /ɪnˈfjuːz/

infuse

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.
C2 noun /ˈaɪsinəs/

iciness

冷たさ
Meaning
The state of being cold in manner or temperature.
Example
There was a distinct iciness in his voice.
彼の声には明確な冷たさがあった。
C1 noun /aɪˈtɪnərɛri/

itinerary

旅程
Meaning
A planned route or schedule of a journey or trip.
Example
The travel agent gave us a detailed itinerary for our vacation.
旅行代理店は私たちの休暇のために詳細な旅程を提供してくれました。
C1 adjective ɪnɪɡˈzɔːstɪbəl

inexhaustible

尽きることのない
Meaning
Unable to be used up or worn out; limitless.
Example
His inexhaustible energy allowed him to work tirelessly on his projects.
彼の尽きることのないエネルギーは、彼がプロジェクトに休むことなく取り組むことを可能にしました。
C1 noun /ɪnˈsæn.ə.ti/

Insanity

狂気; 精神疾患
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.
弁護人は、被告人が狂気によって無罪であると主張した。
C1 adjective /ˈɪntrɪkət/

intricate

複雑
Meaning
very detailed, complex, and difficult to understand
Example
The artist created an intricate pattern on the wall.
アーティストは壁に複雑な模様を作り出しました。
C2 verb /ɪˈreɪdieɪt/

irradiate

照射する
Meaning
to shine light on something; to expose to radiation; to illuminate or brighten
Example
The scientist used a lamp to irradiate the sample.
科学者はランプを使ってサンプルを照射しました。
C1 noun /ɪmˈpɜː.mə.nəns/

impermanence

無常
Meaning
The state or fact of lasting for only a limited period of time.
Example
The philosophy of Buddhism emphasizes the impermanence of life.
仏教の哲学は、人生の無常性を強調します。
C1 adjective /ˌɪntərˈtwaɪnd/

intertwined

幸福
Meaning
closely connected or twisted together
Example
Their lives became deeply intertwined after the accident.
彼女は賞を受け取ったとき、幸せを隠せませんでした。
C2 noun /ˈɪntəˌkrɒpɪŋ/

intercropping

間作農業
Meaning
The agricultural practice of cultivating two or more crops simultaneously in the same field to maximize land use efficiency and improve soil health.
Example
Intercropping can help improve soil fertility and pest control.
間作農業は土壌の肥沃度と害虫管理の向上に役立ちます。
B2 verb /ɪˈnɪʃieɪt/

initiate

開始する
Meaning
to begin or start; to introduce someone to a new activity
Example
The company will initiate a new training program.
会社は新しい研修プログラムを開始します。
B2 noun /ˌɪmpərˈfɛkʃən/

imperfection

不完全
Meaning
a flaw, defect, or weakness; the state of being imperfect
Example
She accepted her imperfection as part of being human.
彼女は人間であることの一部として自分の不完全さを受け入れた。
C1 verb /ɪnˈkɑːrsəreɪt/

incarcerate

投獄する
Meaning
to imprison or confine someone
Example
The authorities incarcerated the criminal after the trial.
当局は裁判後に犯罪者を投獄しました。
C1 adjective /ˌɪndɪˈfɛnsəbl̩/

indefensible

弁護できない
Meaning
not able to be protected or justified
Example
The minister’s remarks were considered indefensible by the public.
大臣の発言は公衆によって弁護できないとみなされました。
B2 adjective /aɪˈrɒnɪk/

ironic

皮肉な、風刺的な
Meaning
happening in the opposite way to what is expected, often amusing or sarcastic
Example
It is ironic that the fire station burned down.
消防署が焼けるのは皮肉です。
B2 verb /ɪnˈstrʌkt/

instruct

指示する
Meaning
to teach; to give directions
Example
The teacher instructed the students carefully.
先生は生徒に注意深く指示しました。
B2 verb /ɪnˈtɛnsɪfaɪ/

intensify

強化する
Meaning
To make something stronger, more extreme, or more forceful.
Example
The storm is expected to intensify overnight.
嵐は夜通し強くなると予想されています。
C1 adjective /ˌɪnstənˈteɪniəs/

instantaneous

即時
Meaning
Happening immediately, without any delay.
Example
The change in temperature was almost instantaneous.
温度の変化はほぼ即時でした。
C1 noun /ˌɪnkoʊˈhɪrəns/

incoherence

不整合
Meaning
The quality of being unclear, confused, or lacking logical connection.
Example
His speech was full of incoherence and difficult to follow.
彼のスピーチは不整合で、理解するのが難しかった。
C2 adjective /ˌɪnɪkˈspiːdiənt/

inexpedient

不適切
Meaning
Not advisable, suitable, or practical in the circumstances.
Example
It would be inexpedient to invest without proper research.
適切な調査なしで投資することは不適切です。
C1 noun /ˈɪntərˌpleɪ/

interplay

相互作用
Meaning
The way in which two or more things have an effect on each other.
Example
The interplay between culture and technology shapes modern life.
文化と技術の相互作用が現代生活を形作っています。
C2 noun /ˌɪrɪˈdɛsəns/

iridescence

虹色の輝き
Meaning
a play of lustrous, changing colors like those of a rainbow
Example
The butterfly's wings shimmered with iridescence.
蝶の羽は虹色の輝きで輝いていました。
B2 noun /ˌɪnsɪˈkjʊərɪti/

insecurity

不安感
Meaning
lack of confidence or assurance; a state of uncertainty or vulnerability
Example
Her insecurity made her doubt her abilities despite her experience.
彼女の不安感は彼女に自分の能力を疑わせた。
B1 verb /ɪnˈkriːst/

increased

増加した
Meaning
became greater in size, amount, or degree
Example
The company's revenue increased last year.
会社の収益は昨年増加しました。
C1 noun /ˌɪntərˈmɪʃən/

intermission

休憩
Meaning
A pause or break, especially during a performance or event.
Example
The play had a twenty-minute intermission.
その劇には20分間の休憩がありました。
B2 adjective /ɪnˈtɒlərənt/

intolerant

不寛容
Meaning
unwilling to accept or respect beliefs or behavior different from one's own
Example
He is intolerant of any opinion that differs from his own.
彼は自分の意見と異なる意見を全く容認しません。
B2 adjective /ˌɪntərˈmiːdiət/

intermediate

中級
Meaning
Coming between two things in time, place, or order; in the middle level or stage.
Example
She is taking an intermediate-level French course.
彼女は中級のフランス語コースを受講しています。
C1 adjective /ɪˈledʒ.ə.bəl/

illegible

読めない
Meaning
Not clear enough to be read; unreadable.
Example
The doctor’s handwriting was almost illegible.
医者の手書きはほとんど読めなかった。
C2 adverb /ˌɪnsəʊˈmʌtʃ/

insomuch

これほど
Meaning
to such an extent
Example
He was insomuch tired that he could hardly stand.
彼はあまりにも疲れていて、ほとんど立つことができませんでした。
C2 adjective /ˌɪnkəˈməʊdiəs/

incommodious

不快な
Meaning
Uncomfortably small, cramped, or inconvenient.
Example
We had to stay in an incommodious room during the trip.
旅行中に不快な部屋に泊まらなければなりませんでした。
B2 noun /ɪnˈkluːʒən/

inclusion

インクルージョン
Meaning
the action or state of including or being included within a group or structure
Example
Diversity and inclusion are key values in modern workplaces.
多様性とインクルージョンは現代の職場における重要な価値観です。
C2 adjective /ˌɪnfəˈlɪsɪtəs/

infelicitous

不適切な
Meaning
not suitable or well chosen; awkward or unfortunate
Example
His infelicitous remark ruined the atmosphere of the meeting.
彼の不適切な発言は会議の雰囲気を台無しにしました。
B2 verb /ɪnˈfɜːr/

infer

Meaning
to conclude or deduce something from evidence and reasoning rather than from explicit statements
Example
From his silence, I inferred that he was not happy with the decision.
C1 adjective /ɪnˈstɪŋk.tɪv/

instinctive

本能的, 自然な, 自動的
Meaning
Based on instinct; done without conscious thought; natural and automatic.
Example
His instinctive reaction saved his life.
彼の本能的な反応は彼の命を救った。
B2 verb /ɪnˈdʌldʒ/

indulge

楽しむ
Meaning
to allow oneself to enjoy something enjoyable, often excessively
Example
He indulged in a piece of chocolate cake after dinner.
彼はディナーの後でチョコレートケーキの一切れを楽しんだ。
C1 noun /ɪˈmiːdiəsi/

immediacy

即時性, 緊迫感
Meaning
The quality of bringing one into direct and instant involvement with something, giving rise to a sense of urgency or excitement.
Example
The immediacy of digital communication has reshaped business operations.
デジタルコミュニケーションの即時性は、ビジネスの運営方法を変えました。
C1 verb /aɪˈdiː.ə.laɪz/

idealize

理想化する
Meaning
To regard or represent something as perfect or better than it really is.
Example
Children often idealize their parents.
子供たちはしばしば親を理想化します。
C1 adjective /ˈɪndɪɡoʊ bluː/

Indigo-blue

インディゴブルー
Meaning
a deep blue color with a purplish tinge
Example
The indigo-blue sky looked magnificent at twilight.
インディゴブルーの空は夕暮れ時に壮大に見えた。