impassive
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C1 adjective /ɪmˈpæsɪv/

impassive

無表情
Meaning
Not showing or feeling emotion; expressionless.
Example
Despite the shocking news, she remained impassive.
衝撃的なニュースにもかかわらず、彼女は無表情のままでした。
C1 noun /ˌɪndɪɡˈneɪʃən/

indignation

憤慨
Meaning
Strong displeasure or anger caused by something unjust, offensive, or insulting.
Example
Public indignation grew after the unfair verdict.
不公平な判決の後で、公衆の憤慨が高まった。
C1 adjective ˈɪn.tər.ɪm

interim

暫定的
Meaning
In or for the intervening period; provisional or temporary.
Example
Interim governments manage transitional phases.
暫定政府は移行段階を管理します。
C1 noun /ɪnˌkɑːsəˈreɪʃən/

incarceration

投獄
Meaning
the state of being imprisoned or confined
Example
The criminal faced years of incarceration for his crimes.
犯人はその犯罪のために長年の投獄を受けた。
C1 adjective /ɪmˈpɜːrtɪnənt/

impertinent

無礼な
Meaning
rude and showing a lack of respect
Example
It was impertinent of him to question the manager's decision.
マネージャーの決定に疑問を呈するのは無礼でした。
C1 noun /ˌɪmpɔːrˈteɪʃən/

importation

輸入
Meaning
The act of bringing goods or services into a country from abroad
Example
The importation of luxury goods is strictly regulated.
高級品の輸入は厳しく規制されています。
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。
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.
C1 adjective /ɪnˈɡreɪnd/

ingrained

根強い
Meaning
Firmly fixed or established; deeply rooted and difficult to change.
Example
His ingrained habits were hard to break.
彼の根強い習慣は壊すのが難しかった。
C1 verb /ɪmˈpɒvərɪʃ/

impoverish

貧困にする
Meaning
To make someone poor or reduce the quality or richness of something.
Example
The long war impoverished the entire nation.
長い戦争が国全体を貧困にした。
C1 adjective /ɪnˈsɛp(ə)rəbəl/

inseparable

切り離せない
Meaning
Unable to be separated or always together.
Example
The two friends have been inseparable since childhood.
二人の友達は子供の頃から切り離せないです。
C1 verb ɪˈnɪʃɪeɪtɪd

initiated

開始された
Meaning
Caused a process or action to begin; started something.
Example
The project was initiated to enhance marine biodiversity.
プロジェクトは海洋生物多様性を向上させるために開始されました。
C1 adjective ɪnˈsaɪ.sɪv

incisive

鋭い
Meaning
Intelligently analytical and clear-thinking; showing clear thought and good understanding of what is important.
Example
His incisive comments revealed the core issues.
彼の鋭いコメントは核心的な問題を明らかにしました。
C1 adverb, adjective /ˌɪnkɑːɡˈniːtoʊ/

incognito

インコグニート
Meaning
In disguise or with one's identity concealed.
Example
The celebrity traveled incognito to avoid the paparazzi.
有名人はパパラッチを避けるためにインコグニートで旅行した。
C1 adjective /ɪnˈtændʒəbl/

intangible

無形の
Meaning
Unable to be touched or grasped; not having a physical presence.
Example
Trust is an intangible quality in relationships.
信頼は関係において無形の特質です。
C1 adjective ɪˈneɪt

Innate

生まれつきのまたは自然の
Meaning
Existing from birth or natural
Example
She has an innate talent for music.
彼女は音楽において生まれつきの才能を持っている。
C1 adjective /ɪˈlɒdʒ.ɪ.kəl/

Illogical

非論理的
Meaning
not reasonable or sensible; lacking logic
Example
It would be illogical to go swimming in such cold weather.
こんなに寒い天気で泳ぐのは非論理的です。
C1 noun /ɪnˈdjuːsmənt/

inducement

誘因
Meaning
something that persuades or encourages someone to do something
Example
The company offered a bonus as an inducement to employees.
会社は従業員にインセンティブとしてボーナスを提供しました。
C1 adjective /ɪnˈedəbəl/

Inedible

食べられない
Meaning
not suitable or safe for eating; not edible
Example
The mushrooms were poisonous and completely inedible.
そのキノコは毒性があり、完全に食べられないものでした。
C1 adjective /ɪmˈpɜːmiəbl/

impermeable

不透水の
Meaning
Not allowing fluid or gas to pass through.
Example
The container is made of impermeable plastic.
その容器は不透水のプラスチックでできています。
C1 adjective /ɪnˈɛlɪdʒəbəl/

Ineligible

不適格; 無資格; 選ばれない
Meaning
not qualified or entitled to participate or be chosen; unsuitable
Example
Students with poor grades are ineligible for the scholarship program.
成績が悪い学生は奨学金プログラムに応募できません。
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 adjective /ɪnˈæk.tɪv/

Inactive

非アクティブ
Meaning
not active; not working; dormant; idle
Example
The volcano has been inactive for over a century.
この火山は1世紀以上も活動していない。
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 /ɪˈrɛvərənt/

irreverent

不敬な
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.
コメディアンの不敬なジョークは、観客の一部を不快にさせた。
C1 adjective /ˌɪnkənˈkluːsɪv/

inconclusive

結論が出ていない
Meaning
Not leading to a definite result or decision.
Example
The investigation remained inconclusive due to a lack of evidence.
証拠の不足により、調査は結論が出ていないままでした。
C1 adjective /ɪnˈtɛlɪdʒəbl/

intelligible

Meaning
Able to be understood; clear enough to be comprehended.
Example
Her speech was barely intelligible over the noise.
C1 adjective /ˌɪnkənˈsiːvəbl̩/

inconceivable

想像できない
Meaning
Impossible to imagine or believe; beyond comprehension.
Example
It seemed inconceivable that she could finish the marathon after such little training.
彼女があれほどのトレーニングでマラソンを完走できるとは想像できなかった。
C1 adjective /ˈɪnsjələr/

insular

狭い心の、島に関連する
Meaning
Narrow-minded, isolated, or relating to an island.
Example
The community was criticized for its insular attitudes toward outsiders.
そのコミュニティは外部の人々に対する狭量な態度で批判されました。
C1 adjective /ˈɪɡ.ni.əs/

igneous

火成
Meaning
Formed through the cooling and solidification of magma or lava.
Example
Granite is an igneous rock commonly used in construction.
花崗岩は建設に一般的に使用される火成岩です。
C1 noun /ɪnˈdɪɡ.nə.ti/

Indignity

屈辱
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.
彼女は正当な理由もなく荷物検査を受けるという屈辱に耐えることを拒んだ。
C1 adjective /ˌɪndɪˈskrɪmɪnət/

indiscriminate

無差別
Meaning
Done without careful judgment; random or haphazard.
Example
The indiscriminate use of pesticides harms the environment.
農薬の無差別な使用は環境に害を与えます。
C1 adjective ˌɪdiəsɪnˈkrætɪk

idiosyncratic

奇妙で個人的な
Meaning
Relating to idiosyncrasy; peculiar or individual.
Example
His idiosyncratic behavior set him apart from his colleagues.
彼の独特な行動は彼を同僚たちから区別させた。
C1 noun /ɪnˈdem.nə.ti/

Indemnity

補償
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.
保険会社は洪水による損害に対して完全な補償を提供しました。
C1 adjective /ˌɪnkɒmprɪˈhɛnsəbl/

incomprehensible

理解不能
Meaning
Impossible or very difficult to understand.
Example
The professor’s lecture was so fast it became incomprehensible.
教授の講義は速すぎて理解不能になった。
C1 noun /ˌɪm.pəˈzɪʃ.ən/

Imposition

課税; 負担; 不公平な要求
Meaning
the action or process of imposing something or of being imposed; an unfair burden or demand
Example
The imposition of new taxes without consultation angered the citizens greatly.
相談なしに新しい税金が課され、市民は非常に怒りました。
C1 verb ɪˈmɜːrs

immerse

浸る
Meaning
To involve oneself deeply in a particular activity or interest; to surround completely.
Example
Immerse yourself in the new language.
新しい言語に浸ってください。
C1 noun /ˈɪnflʌks/

influx

流入
Meaning
A large arrival or flow of people or things.
Example
The city experienced an influx of tourists during the festival.
その都市は祭りの期間中に観光客の流入を経験しました。
C1 noun (plural) /ˈɪndɪˌsiːz/

indices

インデックス
Meaning
plural form of index; statistical measures or reference points used for comparison
Example
Stock market indices fell sharply after the announcement.
発表後、株式市場のインデックスは急落しました。
C1 noun/verb /ˈɪnsɛns/

incense

お香 / 激怒させる
Meaning
a substance burned for its sweet smell (noun); to make very angry (verb)
Example
The smell of incense filled the temple, but his rude words incensed her.
お香の香りが寺院を満たしましたが、彼の失礼な言葉は彼女を激怒させました。
C1 adjective /ɪnˈkɒŋɡruəs/

incongruous

不調和
Meaning
Not fitting in with or suitable for the surroundings.
Example
His jokes were incongruous during the serious meeting.
彼の冗談は真面目な会議では不調和だった。
C1 adverb /ˌɪn.dɪˈskrɪm.ɪ.nət.li/

Indiscriminately

無差別に
Meaning
without making careful distinctions; randomly; without discrimination
Example
The company fired employees indiscriminately without considering their performance.
会社は従業員を彼らのパフォーマンスを考慮せずに無差別に解雇しました。
C1 adjective /ɪmˈpɛndɪŋ/

impending

差し迫った
Meaning
about to happen soon, usually something unpleasant or threatening
Example
The villagers were worried about the impending flood.
村人たちは差し迫った洪水を心配していた。
C1 adjective /ɪnˈdʌstriəs/

industrious

勤勉な
Meaning
Hardworking and diligent in one's duties.
Example
She is an industrious student who always completes her assignments on time.
彼女は常に期限通りに課題を終わらせる勤勉な学生です。
C1 noun /ˈɪn.trə.vɜːrt/

introvert

内向的
Meaning
A person who tends to be shy and prefers spending time alone rather than in groups.
Example
As an introvert, he preferred reading over attending parties.
内向的な性格として、パーティに参加するよりも読書の方が好きでした。
C1 noun /ˌɪnkənˈsɪstənsi/

inconsistency

不一致
Meaning
The quality of being contradictory, irregular, or not staying the same.
Example
There is an inconsistency between his words and actions.
彼の言葉と行動には不一致があります。
C1 noun /ˈɪnkjʊˌbeɪtər/

incubator

インキュベーター
Meaning
a device or environment that provides suitable conditions for eggs, cells, or infants to develop
Example
The premature baby was placed in an incubator for care.
未熟児はケアのためにインキュベーターに入れられました。
C1 verb /ɪmˈplɔːr/

implore

Meaning
To beg someone earnestly or desperately to do something.
Example
She implored him to stay with her.
C1 noun /ˈɪnˌmeɪt/

inmate

囚人
Meaning
a person confined to an institution such as a prison or hospital
Example
The prison has over a thousand inmates.
刑務所には千人以上の囚人がいます。
C1 verb /ˈɪmprəvaɪz/

improvise

Meaning
To create or perform something spontaneously without preparation.
Example
The actor had to improvise his lines when he forgot the script.
C1 noun /ɪnˈfɜːrnoʊ/

inferno

火災
Meaning
a large, intense fire that is dangerously out of control
Example
The building turned into an inferno within minutes.
その建物は数分で火災に変わった。
C1 adjective /ˈɜːrksəm/

irksome

迷惑的
Meaning
annoying or irritating
Example
Waiting in a long line is one of the most irksome tasks.
長い列に並んでいるのは、最も迷惑な作業の一つです。
C1 noun ˌɪnˈsaɪtfʊlnɪs

insightfulness

洞察力、分析能力
Meaning
The capacity to gain an accurate and deep intuitive understanding of a person or thing.
Example
His insightfulness helped solve the complex problem.
彼の洞察力は複雑な問題を解決するのに役立ちました。
C1 adjective /ɪmˈpɛn.ɪ.trə.bəl/

impenetrable

Meaning
Impossible to pass through or enter; impossible to understand.
Example
The dense forest was nearly impenetrable.
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 adjective /ɪmˈpjʊər/

Impure

不純
Meaning
contaminated; not clean; mixed with foreign substances
Example
The impure water caused health problems in the village.
不純な水は村で健康問題を引き起こしました。
C1 noun /ˌɪnsɪɡˈnɪfɪkəns/

insignificance

重要でないこと
Meaning
The quality of being unimportant or trivial.
Example
He felt a sense of insignificance in the vast universe.
彼は広大な宇宙で重要でないことを感じました。
C1 noun /ˌɪnfɪˈdɛləti/

infidelity

不倫
Meaning
the act of being unfaithful to a spouse or partner
Example
Their marriage ended due to his infidelity.
彼らの結婚は彼の不倫が原因で終わった。
C1 adjective /ɪˈnɔːɡjərəl/

Inaugural

開幕
Meaning
marking the beginning of something; first; opening
Example
The president delivered his inaugural speech.
大統領は彼の開幕スピーチを行いました。
C1 noun /ɪˌluːmɪˈneɪʃən/

illumination

Meaning
the act of lighting something or making something clear
Example
The street was filled with bright illumination from the lamps.
C1 adjective /ˈɪrɪtəbl/

irritable

Meaning
easily annoyed or made angry
Example
She became irritable after working long hours without rest.
C1 noun /ˌɪnkjʊˈbeɪʃən/

incubation

卵、細胞、または生物を適切な条件で発展させるプロセス
Meaning
the process of keeping eggs, cells, or organisms in the right conditions for development
Example
The incubation of the eggs lasted for three weeks.
卵のインキュベーションは三週間続きました。
C1 adjective /ɪnˈhjuːmən/

Inhuman

非人道的
Meaning
lacking human qualities of compassion and mercy; cruel or barbaric
Example
The prisoners were kept in inhuman conditions.
囚人たちは非人道的な状況で収容されていました。
C1 adjective /ˌɪnsərˈmaʊntəbl/

insurmountable

克服不可能
Meaning
Too great to be overcome.
Example
The explorers faced insurmountable odds in the desert.
探検者たちは砂漠で克服不可能な障害に直面した。
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 /ɪˈmoʊbəl/

immobile

動けない
Meaning
unable to move or be moved
Example
After the accident, he was immobile for weeks.
事故の後、彼は数週間動けなかった。
C1 adjective /ˌɪnəˈfɛnsɪv/

inoffensive

無害な
Meaning
Not likely to offend or provoke; harmless.
Example
His inoffensive remarks kept the conversation friendly.
彼の無害なコメントは会話を友好的に保ちました。
C1 adjective /ɪmˈpæsəbəl/

impassable

通行不可能
Meaning
Impossible to travel along or over.
Example
The road became impassable after the heavy snowfall.
大雪の後、道は通行不可能になりました。
C1 adjective /ˌɪnɔːrˈɡænɪk/

inorganic

無機の
Meaning
relating to substances that are not derived from living organisms; lacking organic structure or growth
Example
Inorganic compounds are commonly studied in chemistry labs.
無機化合物は化学の基本です。
C1 verb /ɪmˈpɪndʒ/

impinge

影響を与える
Meaning
to have an effect or impact on something; to encroach or infringe
Example
The noise from the construction site impinges on our daily activities.
建設現場の音は私たちの日常的な活動に影響を与えます。
C1 adjective ɪnˈkʌm.bənt

incumbent

義務的な
Meaning
necessary for (someone) as a duty or responsibility.
Example
It is incumbent upon all citizens to obey the law.
すべての市民が法律を守るのは義務である。
C1 adjective /ˈaɪərnˌklæd/

ironclad

鉄壁の
Meaning
impossible to change, break, or dispute; very strong and firm
Example
The company had an ironclad contract with its suppliers.
その会社はサプライヤーと鉄壁の契約を結んでいた。
C1 verb /ɪnˈhɪbɪt/

inhibit

抑制する
Meaning
to prevent or restrain someone or something from acting freely; to hinder
Example
Fear can inhibit personal growth.
恐怖は個人の成長を抑制する可能性があります。
C1 noun ɪnˈsɛpʃən

inception

始まり
Meaning
The establishment or starting point of an institution or activity.
Example
The inception of the company marked a new era in the industry.
その企業のインセプションは業界に新しい時代を築きました。
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 /ˌɪntəˈsɛkt/

intersect

交差する
Meaning
to cross or pass through each other
Example
The two roads intersect at the city center.
二つの道路は市内中心で交差する。
C1 adjective /ˈɪnsələnt/

insolent

無礼な、傲慢な
Meaning
showing a rude and arrogant lack of respect
Example
The insolent student refused to follow the teacher's instructions.
その無礼な学生は教師の指示に従うことを拒否した。
C1 noun /ˈɪnsɪdəns/

incidence

発生率
Meaning
the occurrence, rate, or frequency of something
Example
The incidence of road accidents has decreased this year.
今年の道路事故の発生率は減少しました。
C1 adjective /ɪnˈtræk.tə.bəl/

intractable

管理不能
Meaning
Difficult or impossible to manage, control, or solve.
Example
The conflict has become an intractable problem.
その対立は管理不能な問題になった。
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。
C1 noun /ɪˌreɡjəˈlærɪti/

irregularity

不規則性
Meaning
lack of regularity or consistency; a deviation from what is normal, expected, or orderly
Example
The audit revealed several financial irregularities in the company’s records.
監査により、その会社の記録にいくつかの財務上の不規則性が明らかになった。
C1 verb /ɪnˈdaɪt/

indict

起訴する
Meaning
to formally accuse someone of committing a serious crime
Example
The grand jury decided to indict the politician for corruption.
大陪審団は腐敗のために政治家を起訴することを決定した。
C1 noun /ˈɪnlɛt/

inlet

入り江
Meaning
A small arm of the sea, a lake, or a river; an opening or passage for entry.
Example
The boat entered a narrow inlet along the coast.
船は海岸沿いの狭い入り江に入った。
C1 adjective /ˌɪndɪˈspjuːtəbəl/

Indisputable

議論の余地がない; 否定できない; 確定的
Meaning
impossible to deny or argue against; undeniable; certain
Example
The evidence against him was indisputable.
彼に対する証拠は議論の余地がなかった。
C1 verb /ɪnˈtɒksɪkeɪt/

intoxicate

幸せ
Meaning
to make someone lose control of their faculties or behavior due to alcohol or drugs
Example
The strong drink quickly intoxicated him.
彼女は賞を受け取ったとき、自分の幸せを隠すことができなかった。
C1 noun /ˈɪn.tə.mə.si/

Intimacy

親密さ; 親しみ
Meaning
close familiarity or friendship; closeness; a private cozy atmosphere
Example
The couple valued the emotional intimacy they shared more than material possessions.
そのカップルは物質的な所有物よりも、共有した感情的な親密さを大切にしていました。
C1 noun ˌɪnsjʊˈleɪʃən

insulation

絶縁
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.
食品保管エリアの絶縁は、害虫が侵入するのを防ぐことができます。
C1 verb /ɪmˈbɛd/

imbed

埋め込む
Meaning
To fix firmly or deeply in a surrounding mass.
Example
The journalist imbedded himself with the troops to report firsthand.
ジャーナリストは部隊に埋め込まれて、最前線から報告を行った。
C1 verb /ˈɪnkjʊˌbeɪt/

incubate

孵化する
Meaning
to keep eggs, cells, or organisms at the right conditions for development
Example
The hen will incubate the eggs until they hatch.
そのニワトリは卵が孵化するまでインキュベートします。
C1 noun /ɪnˈkɜːrʒən/

incursion

侵入
Meaning
A sudden attack or invasion into a place or territory.
Example
The army repelled the enemy incursion at the border.
軍隊は国境で敵の侵入を撃退した。
C1 adjective /ˌɪndɪˈstɪŋkt/

indistinct

不明瞭な
Meaning
Not clear or sharply defined; vague or blurred.
Example
The sound of voices was indistinct in the distance.
遠くからの声は不明瞭でした。
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 adverb /ɪnˈvɜːrs.li/

Inversely

逆に; 反対に
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.
商品の価格は市場での入手可能性に逆に関連しています。
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 /ˌɪməˈtjʊərəti/

immaturity

未熟さ
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.
彼の未熟さは責任を果たすことを難しくした。
C1 noun ɪˌræʃ.ənˈæl.ɪ.ti

irrationality

非合理性, 非論理性, 不合理
Meaning
The quality of being illogical or unreasonable; lack of rational thought.
Example
His decision was driven by complete irrationality.
彼の決定は完全に非合理的でした。
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 noun /ˈɪntrɪkəsi/

intricacy

複雑さ
Meaning
the quality of being very detailed or complicated
Example
The intricacy of the design impressed everyone.
デザインの複雑さは全員を感動させました。
C1 adjective ɪnˈtrɪn.zɪk

intrinsic

内在的, 本質的, 自然な
Meaning
Belonging naturally; essential. Existing as a natural or basic part of something.
Example
Creativity is an intrinsic quality of a great artist.
創造性は偉大なアーティストの内在的な資質です。
C1 adverb /ˌɪnsɪˈdɛntəli/

incidentally

ちなみに
Meaning
by the way; used to introduce a remark not directly related to the main subject
Example
Incidentally, did you know that she studied in Paris?
ちなみに、彼女がパリで勉強していたことを知っていましたか？
C1 noun /ˌɪntərˌɒpərəˈbɪləti/

interoperability

相互運用性
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.
異なるソフトウェアシステムの相互運用性は、シームレスな作業の流れを確保します。
C1 adjective /ˌɪnədˈvaɪzəbl/

inadvisable

推奨されない
Meaning
Not recommended; likely to have undesirable consequences.
Example
It is inadvisable to drive in such heavy rain.
このような大雨の中で運転するのは推奨されません。
C1 adjective /ɪmˈpʌlsɪv/

impulsive

衝動的な, 直感的な
Meaning
acting suddenly without careful thought
Example
She made an impulsive decision to buy the car.
彼女は衝動的な決定で車を買うことにしました。
C1 adjective /ɪˈluː.sɪv/

Illusive

幻想的な; 存在しているように見えるが実際には存在しない; 騙すような
Meaning
deceptive; appearing to exist but not real; misleading
Example
The promise of easy money proved to be illusive and misleading.
簡単なお金の約束は幻想的であり、誤解を招くものでした。
C1 adjective /ɪnˈkɒmpɪtənt/

incompetent

Meaning
Lacking the necessary ability or skills to do something successfully.
Example
He was fired because he was incompetent at his job.
C1 noun /ˌɪnflɛksɪˈbɪlɪti/

inflexibility

柔軟性の欠如
Meaning
the quality of being rigid or unwilling to change; lack of adaptability
Example
The inflexibility of the rules caused unnecessary delays.
規則の柔軟性の欠如が不要な遅れを引き起こした。
C1 noun ˈɪn.fər.əns

inference

推論
Meaning
A conclusion reached on the basis of evidence and reasoning; logical deduction.
Example
Scientists make inferences based on experimental data.
科学者たちは実験データに基づいて推論を行います。
C1 adjective /ˌɪntərˈtʃeɪndʒəbl/

interchangeable

交換可能な
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.
これらの機械部品は交換可能なため、簡単に交換できます。
C1 noun /ˈɪnkwest/

inquest

調査
Meaning
A legal or official inquiry, especially into the cause of a death.
Example
The inquest revealed the cause of the accident.
調査は事故の原因を明らかにしました。
C1 adjective, noun /ˈɪnvəlɪd/ (adjective), /ɪnˈvælɪd/ (noun)

invalid

無効
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.
裁判所は契約を無効と宣言した。
C1 noun /ɪnˈfɜːməri/

infirmary

診療所
Meaning
A hospital or place where the sick or injured are cared for.
Example
The school had an infirmary for minor injuries.
学校には軽傷のための診療所がありました。
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 /ɪnˈvɜːrt/

invert

逆さにする
Meaning
To turn something upside down or in the opposite position, order, or direction.
Example
He inverted the glass to let the water drain out.
彼は水が流れ出るようにグラスを逆さまにしました。
C1 noun /ɪˈreləvəns/

irrelevance

無関係性
Meaning
the quality of not being connected to or important for a particular matter; lack of significance
Example
His long explanation only highlighted the irrelevance of the details to the main issue.
彼の長い説明は、細部が主な問題と無関係であることを強調しただけだった。
C1 verb /ɪnˈsaɪt/

incite

扇動する
Meaning
to provoke; to stir up
Example
His speech incited the crowd to violence.
彼のスピーチは群衆を暴力に駆り立てた。
C1 verb ɪˈnɔː.ɡjə.reɪ.tɪd

inaugurated

開会
Meaning
Begin or introduce (a system, policy, or period) formally.
Example
The organization was inaugurated officially.
その組織は正式に開会されました。
C1 adjective /ˌɪnədˈvɜːrtənt/

inadvertent

意図しない, 不注意な
Meaning
Not resulting from or achieved through deliberate planning; unintentional.
Example
Her inadvertent mistake caused a delay in the project.
彼女の不注意なミスがプロジェクトの遅延を引き起こしました。
C1 noun ˌɪn.toʊˈneɪ.ʃən

intonation

イントネーション
Meaning
The rise and fall of tone in speech and pronunciation.
Example
Proper intonation enhances the clarity of a speech.
適切なイントネーションはスピーチの明確さを高めます。
C1 noun ˌɪndɪˈspensəbl̩ ˈkɒmpɪtənsi

indispensable competency

不可欠な能力
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.
デジタルリテラシーは21世紀のインディスペンセブルなコンピテンスです。
C1 adjective /ˌɪn.dɪˈspen.sə.bəl/

indispensable

不可欠
Meaning
Absolutely necessary, essential
Example
Water is indispensable for human survival.
水は人間の生存に不可欠です。
C1 verb /ˈɪrɪˌɡeɪt/

irrigate

灌漑する
Meaning
to supply water to land or crops; to wash out a wound with water
Example
Farmers irrigate their fields during dry seasons.
農家は乾季に畑に灌漑を行います。