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B2 noun ˈɪndɪkeɪtə

indicator

指標
Meaning
A thing that indicates the state or level of something.
Example
The unemployment rate is a key indicator of economic health.
失業率は経済の健康の重要な指標です。
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 /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。
C2 adjective ˌɪn.ɪ.fɪˈkeɪ.ʃəs

inefficacious

効果がない
Meaning
Not producing any or the desired effect; ineffective.
Example
The treatment was inefficacious in curing the disease.
その治療法は病気の治癒に効果がありませんでした。
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。
C2 adjective /ɪnˈsɛnseɪt/

insensate

無感情な
Meaning
lacking physical sensation or empathy; without feeling or sensitivity
Example
The dictator's insensate cruelty shocked the world.
独裁者の無感情な残虐さは世界を驚かせた。
C1 noun /ˌɪnkəmˌpætəˈbɪlɪti/

incompatibility

非互換性
Meaning
the state of being unable to exist or work together harmoniously; lack of compatibility
Example
The project failed because of incompatibility between the two software systems.
2つのソフトウェアシステムの非互換性のため、そのプロジェクトは失敗した。
A2 adjective ˌɪn.təˈnæʃ.ən.əl

international

国際的な
Meaning
Existing, occurring, or carried on between two or more nations and their citizens.
Example
International standards improve competitiveness.
国際基準は競争力を高めます。
B1 adjective /ɪˈmiːdiət/

immediate

即時
Meaning
happening or done without delay
Example
The doctor gave her immediate attention.
医者は彼女に即時の注意を与えました。
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。
C2 adjective /ˌɪlˈneɪ.tʃəd/

ill-natured

性格が悪い
Meaning
Having a bad or unpleasant character; unkind or malicious.
Example
He made an ill-natured remark about his colleague.
彼は同僚について悪意のある発言をしました。
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。
C2 adjective /ɪmˈprɛɡnəbl̩/

impregnable

攻略不可能
Meaning
Unable to be captured, broken into, or defeated.
Example
The fortress was considered impregnable by the enemy.
その要塞は敵によって攻略不可能と見なされていました。
B1 adjective /ˈɪnəsənt/

Innocent

無実の; 純粋な; 無害な
Meaning
free from guilt or sin; pure; harmless; naive
Example
The innocent child had no idea that her parents were planning a surprise party.
その無実の子供は、両親がサプライズパーティーを計画していることを知りませんでした。
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 noun /ˌɪntərˈfɪərəns/

interference

干渉
Meaning
the action of interfering with something
Example
The radio signal was disrupted due to interference from nearby electronics.
近くの電子機器からの干渉で、ラジオ信号が途絶えました。
B2 noun /ɪnˈspɛktər/

inspector

検査官
Meaning
An official employed to ensure regulations are obeyed or standards are met.
Example
The inspector carefully checked the restaurant's kitchen for hygiene standards.
検査官はレストランのキッチンを衛生基準に従って慎重に確認しました。
B1 verb /ˈɪndʒər/

injure

怪我をさせる
Meaning
to cause physical harm or damage to someone or something
Example
He injured his leg while playing football.
彼はサッカーをしている時に足を怪我した。
B2 noun /ˈɪɡ.nər.əns/

Ignorance

無知
Meaning
lack of knowledge or information; the state of being uninformed about something
Example
His ignorance about basic computer skills made it difficult for him to find a job.
基本的なコンピュータースキルに関する彼の無知は、彼が仕事を見つけるのを難しくしました。
C1 adjective /ɪˈræʃənəl/

irrational

非合理的
Meaning
not logical or reasonable; lacking clear thought
Example
His fear of the dark was completely irrational.
彼の暗闇への恐れは完全に非合理的でした。
C2 adjective /ɪnhɑːrˈmoʊniəs/

Inharmonious

不協和音
Meaning
lacking harmony; discordant in sound; not in tune
Example
The inharmonious sounds from the broken piano made everyone cover their ears.
壊れたピアノからの不協和音がみんなを耳をふさがせました。
C1 adjective /aɪˈdɪlɪk/

idyllic

田園詩のように美しい
Meaning
Like an idyll; extremely happy, peaceful, or picturesque.
Example
They enjoyed an idyllic vacation by the sea.
彼らは海辺で田園詩のような休暇を楽しみました。
C2 verb /ˌɪntərˈpoʊz/

interpose

Meaning
To place or insert between one thing and another; to intervene in a situation.
Example
He quickly interposed himself between the fighters to stop the quarrel.
B1 noun ɪnˈtel.ɪ.dʒəns

intelligence

知能
Meaning
The ability to learn, understand, and think in a logical way about things
Example
Intelligence is key in AI development.
知能はAI開発の鍵です。
C1 noun /ˈɪn.fən.tri/

Infantry

歩兵
Meaning
soldiers marching or fighting on foot; foot soldiers collectively
Example
The infantry advanced across the battlefield on foot.
歩兵は戦場を徒歩で進んだ。
B2 noun ˌɪn.təˈven.ʃən

intervention

介入
Meaning
The action or process of intervening; involvement in a situation to improve or help it.
Example
The intervention of the UN was crucial in resolving the conflict.
国連の介入は紛争を解決する上で重要だった。
B2 adjective ɪˈmɜː.sɪv

immersive

没入型
Meaning
Providing, involving, or characterized by deep absorption or immersion in something.
Example
Virtual reality creates an immersive learning environment.
仮想現実は没入型の学習環境を作り出します。
B1 noun /ɪˌmædʒ.ɪˈneɪ.ʃən/

Imagination

想像力; 創造的思考
Meaning
the faculty or action of forming new ideas or images not present to the senses; creative thinking
Example
Children's imagination allows them to turn a cardboard box into a spaceship or castle.
子供たちのイマジネーションは、段ボール箱を宇宙船やお城に変えることを可能にします。
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 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。
B1 verb /ɪnˈfɔ:m/

inform

通知する
Meaning
to tell someone about something; to give information
Example
Please inform me when you arrive at the airport.
空港に到着したら、私に通知してください。
C2 adjective /ɪmˈpɪəriəs/

imperious

横柄な
Meaning
Arrogantly domineering or overbearing.
Example
Her imperious tone made it hard for others to argue.
彼女の横柄な口調は他の人々が議論するのを難しくしました。
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。
C2 noun /ˈɪn.dɪ.dʒəns/

indigence

貧困
Meaning
a state of extreme poverty or destitution
Example
The charity was founded to help people living in indigence.
その慈善団体は貧困の中で生活している人々を助けるために設立されました。
B2 noun /ɪmˈpeɪʃəns/

impatience

忍耐力不足
Meaning
The state of being quickly irritated or unable to wait calmly.
Example
His impatience grew as the meeting dragged on.
会議が長引くにつれて、彼の忍耐力不足が増しました。
C2 noun /ɪmˈpjuːnɪti/

impunity

Meaning
freedom from punishment or harmful consequences for an action
Example
The dictator ruled with impunity, ignoring international laws.
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 verb /ˌɪnstɪˈtjuːʃənəlaɪz/

institutionalize

制度化する
Meaning
to establish something as a formal institution, custom, or practice
Example
The government seeks to institutionalize environmental protection.
政府は環境保護を制度化しようとしています。
C2 adjective /ɪnˈkɑːdʒɪtənt/

incogitant

無思慮な
Meaning
Lacking thought; inconsiderate or thoughtless.
Example
It was incogitant of him to make such a rude comment.
彼がそんな失礼なコメントをするのは無思慮なことでした。
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 /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 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 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。
B2 adjective /ɪnˈtɛnsɪv/

intensive

集中的
Meaning
Involving a lot of effort, energy, or concentration in a short period of time.
Example
She attended an intensive English course before moving abroad.
彼女は海外に引っ越す前に、集中的な英語コースを受講しました。
B1 noun /ɪnˈstrʌkʃənz/

instructions

指示
Meaning
Detailed information on how something should be done or operated.
Example
Please follow the instructions on the box.
箱に書かれた指示に従ってください。
A1 adjective /ɪmˈpɔː.tənt/

important

重要
Meaning
Of great significance or value; likely to have a profound effect on success, survival, or well-being.
Example
Important steps must be taken to address pollution.
汚染に対処するためには重要なステップを踏む必要があります。
B2 verb /ˌɪntərˈviːn/

intervene

介入する
Meaning
To come between people, groups, or events, often to prevent conflict or improve a situation.
Example
The teacher had to intervene to stop the fight between the students.
教師は生徒たちの間で喧嘩を止めるために介入しなければならなかった。
C1 adjective /ɪˈnɜːrt/

inert

不活性
Meaning
lacking the ability or strength to move or act; chemically inactive
Example
The patient remained inert on the bed.
患者はベッドで動かずにじっとしていました。
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 /ˌɪn.trəˈmjʊə.rəl/

intramural

学内
Meaning
Occurring within the walls of a single institution, especially a school or college.
Example
The college organizes intramural sports competitions every semester.
大学は毎学期、学内スポーツ競技を開催しています。
C2 noun /ɪmˈpaɪ.ə.ti/

Impiety

不敬
Meaning
lack of piety or reverence, especially for a god; disrespect or irreverence toward religious matters
Example
His impiety shocked the religious community when he mocked their sacred ceremonies.
彼の不敬は、彼が彼らの神聖な儀式を嘲笑したとき、宗教コミュニティを驚かせました。
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。
C2 adjective /aɪˈdɒlətrəs/

idolatrous

偶像崇拝者
Meaning
Excessively admiring or worshipping someone or something as an idol.
Example
The king was criticized for his idolatrous devotion to wealth.
王は富に対する偶像崇拝的な献身で批判されました。
C1 adjective /ɪˈnɛpt/

inept

不器用
Meaning
lacking skill or ability; clumsy or incompetent
Example
His inept handling of the situation made it worse.
彼の不器用な状況の対処が状況を悪化させた。
C1 noun /ɪnˌtɪmɪˈdeɪʃən/

intimidation

威圧
Meaning
The action of frightening or threatening someone to make them do something.
Example
The workers reported cases of intimidation by the management.
労働者たちは経営陣による威圧の事例を報告しました。
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。
C2 adjective /ˌɪn.ɪˈlʌk.tə.bəl/

ineluctable

Meaning
Impossible to avoid or escape; inevitable.
Example
Death is an ineluctable part of human existence.
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。
C2 adjective /ɪnˈklɛmɛnt/

inclement

悪天候
Meaning
unpleasantly cold, wet, or stormy (usually weather)
Example
The match was canceled due to inclement weather.
試合は悪天候のためキャンセルされました。
C2 noun /ɪnˈsuːsiəns/

insouciance

無関心
Meaning
Casual lack of concern; indifference.
Example
She carried herself with an air of insouciance, unbothered by the challenges ahead.
彼女は無関心な態度で歩いていた、前にある挑戦を気にせずに。
C2 adjective /ɪnˈsɛnʃənt/

insentient

無感覚の
Meaning
Lacking perception, consciousness, or sensation.
Example
The rock is an insentient object with no awareness.
岩は意識のない無感覚の物体です。
B2 noun /ˈɪnvənˌtɔːri/

inventory

インベントリ
Meaning
A complete list of items, such as goods in stock or property.
Example
The shopkeeper checked the inventory before opening the store.
店主は店を開店する前にインベントリを確認しました。
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。
C1 noun /ˈaɪsətəʊp/

isotope

同位体
Meaning
Atoms of the same element with equal number of protons but different numbers of neutrons.
Example
Carbon-14 is a radioactive isotope used in dating fossils.
炭素-14は化石の年代を測定するために使用される放射性同位体です。
C2 noun /aɪˈkɒnəklæst/

iconoclast

偶像破壊者
Meaning
A person who attacks or criticizes cherished beliefs, traditions, or institutions.
Example
He was known as an iconoclast who challenged old traditions.
彼は古い伝統に挑戦した偶像破壊者として知られていました。
C2 noun /ˈɪrɪtənsi/

irritancy

苛立ち
Meaning
the quality or state of causing irritation; legal or formal invalidation
Example
The constant noise became an irritancy to the neighbors.
絶え間ない騒音は隣人にとって苛立ちの原因となりました。
B2 noun /ɪnˈtɪəriər/

interior

インテリア
Meaning
the inside part of something; inner area of a place or object
Example
The interior of the hotel was beautifully decorated.
ホテルのインテリアは美しく装飾されていました。
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 /ˌɪntəkəˈnɛktɪvɪti/

interconnectivity

相互接続性
Meaning
The state of being interconnected or the degree of connectivity between components
Example
The rise of interconnectivity has transformed global communication.
インターコネクティビティの発展は、世界中のコミュニケーションを変革しました。
C2 noun /ˈɪrɪɡənt/

irrigant

灌漑液
Meaning
A liquid used for irrigation, especially in medical or agricultural contexts.
Example
The doctor used a sterile irrigant during the procedure.
医師は手術中に無菌の灌漑液を使用しました。
C1 verb /ɪmˈpiːd/

impede

妨げる
Meaning
To obstruct or hinder the progress or development of something.
Example
Lack of funds can impede business growth.
資金不足はビジネスの成長を妨げる可能性があります。
C2 adverb /ˈaɪsɪli/

icily

冷たく
Meaning
In a very cold, unfriendly, or hostile manner.
Example
She replied icily to his question.
彼女は冷たく彼の質問に答えた。
C2 verb /ɪnˈdaɪt/

indite

作詞する
Meaning
To write or compose (literary or formal works).
Example
The poet indited a heartfelt sonnet.
詩人は心のこもったソネットを作詞した。
C1 adjective /ɪmˈplɔːzəbl/

implausible

信じがたい
Meaning
Not seeming reasonable or probable; unlikely to be true.
Example
The story she told was so implausible that no one believed her.
彼女が話した話はあまりにも信じられないほどで、誰も彼女を信じなかった。
C1 adjective /ɪnˈvɜːs/

Inverse

逆の; 反対の
Meaning
opposite in order, nature, or effect; reversed
Example
There is an inverse relationship between price and demand.
価格と需要の間に逆の関係があります。
C2 adjective /ˈɪmənənt/

immanent

内在的
Meaning
existing or operating within; inherent
Example
He believed that moral values are immanent in human nature.
彼は道徳的価値が人間の本性に内在していると信じていました。
C2 noun /ˌɪntərˈsɛʃən/

intercession

仲介
Meaning
the act of intervening or pleading on behalf of another person
Example
The prisoner was released due to the intercession of influential leaders.
囚人は影響力のあるリーダーたちの仲介で釈放されました。
C2 noun /ˈɪmɪˌteɪtər/

imitator

模倣者
Meaning
a person who copies the behavior, style, or actions of others
Example
He became famous as an imitator of popular singers.
彼は人気のある歌手の模倣者として有名になった。
B1 noun ˈɪn.də.stri

industry

産業
Meaning
Economic activity concerned with the processing of raw materials and manufacture of goods in factories.
Example
The industry focuses on luxury experiences.
産業は高級体験に焦点を合わせています。
C1 adjective /ɪnˈvæljʊəbl/

invaluable

計り知れない価値がある
Meaning
Extremely useful or indispensable.
Example
Her advice proved invaluable to my success.
彼女の助言は私の成功にとって非常に貴重でした。
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。
B2 adjective /ˌɪnsɪɡˈnɪfɪkənt/

insignificant

重要でない
Meaning
Too small or unimportant to be worth considering.
Example
The cost was so insignificant that nobody noticed it.
そのコストは重要でなく、誰もそれに気づかなかった。
B1 verb /ɪnˈvɑːlv/

involve

関与する
Meaning
to include as a necessary part, or to engage someone in an activity
Example
The project will involve several departments working together.
このプロジェクトは、いくつかの部署が一緒に働くことを含むでしょう。
C2 noun /ˈɪnfəmi/

infamy

幸福
Meaning
the state of being well known for some bad quality or deed
Example
His name will live in infamy for the crimes he committed.
彼女は賞を受け取ったとき、自分の幸福を隠すことができなかった。
B2 noun ˌɪnɪˈkwɒlɪti

inequality

不平等
Meaning
Difference in size, degree, circumstances, etc.; lack of equality.
Example
The theme of inequality is prominent throughout the story.
不平等のテーマは物語全体にわたって顕著です。
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 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.
B2 verb /ɪnˈheɪl/

inhale

吸う
Meaning
to breathe in; to draw air into the lungs
Example
Take a deep breath and inhale slowly.
深く息を吸い、ゆっくり吸い込みます。
B1 noun aɪˈdɛntɪti

identity

アイデンティティ
Meaning
The fact of being who or what a person or thing is; the characteristics determining who or what a person or thing is.
Example
The day reinforces our national identity.
その日は私たちの国民的アイデンティティを強化します。
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。
C1 adjective /ɪnˈses.ənt/

incessant

絶え間ない
Meaning
Continuing without pause or interruption; constant.
Example
The incessant noise from the construction site made it hard to concentrate.
建設現場からの絶え間ない騒音は集中するのを困難にしました。
C2 noun /ˈɪndələns/

indolence

怠惰
Meaning
Avoidance of activity or exertion; laziness.
Example
His indolence kept him from finishing the project on time.
彼の怠惰は彼が時間通りにプロジェクトを完成させるのを妨げました。
C2 noun /ˈɪnroʊd/

inroad

進展
Meaning
An advance or significant progress, often at the expense of something else.
Example
The company made significant inroads into the mobile market.
その会社はモバイル市場で重要な進展を遂げました。
C1 noun /ɪnˈhɛrɪtər/

inheritor

相続人
Meaning
a person who receives money, property, or a title when someone dies
Example
She became the inheritor of her family's estate.
彼女は家族の財産の相続人となった。
C2 noun /ˌɪn.trəˈɡreʃ.ən/

introgression

遺伝子流入
Meaning
The transfer of genetic information from one species to another through repeated backcrossing.
Example
Introgression plays a significant role in plant breeding.
イントログレッションは植物育種において重要な役割を果たします。
C1 adjective /ɪnˈtɛlɪdʒəbl/

intelligible

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

inwardly

内面的に
Meaning
In the mind or spirit; not outwardly visible.
Example
She smiled outwardly but inwardly she was worried.
彼女は外見では微笑んだが、内心では心配していた。
C1 adjective /ɪˈnænɪmət/

inanimate

無生物
Meaning
not alive, especially not in the manner of animals and humans; lifeless
Example
The museum was full of inanimate objects from ancient times.
博物館には古代の無生物がいっぱいだった。
C1 verb /ɪmˈploʊd/

implode

内爆
Meaning
To collapse or burst inward violently.
Example
The old building imploded during the demolition.
古い建物は解体中に内向きに崩壊しました。
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。
C2 noun /aɪˈoʊtə/

iota

微小な量
Meaning
An extremely small amount.
Example
He did not show an iota of fear.
彼は恐怖の一片も見せませんでした。
C1 adjective /ɪˈlɪsɪt/

illicit

不法な
Meaning
Forbidden by law, rules, or custom.
Example
The police shut down the illicit drug operation.
警察は不法な麻薬取引を閉鎖しました。
C1 noun ɪnˈsɒl.vən.si

insolvency

破産
Meaning
The state of being unable to pay debts owed; bankruptcy.
Example
The company declared insolvency after years of losses.
その会社は多くの損失の後、破産を宣言した。
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。
C2 adjective /ˌɪntəˈrɒɡətəri/

interrogatory

尋問的な
Meaning
expressed in the form of a question; relating to questioning
Example
The lawyer’s interrogatory tone made the witness uncomfortable.
弁護士の尋問的な口調は証人を不快にさせました。
C1 noun /ɪmˌpɒsəˈbɪlɪti/

impossibility

不可能性
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.
一日でそのプロジェクトを終えるのは不可能だった。
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 verb /ɪnˈfleɪm/

inflame

煽る
Meaning
to arouse strong feelings or provoke anger; to cause inflammation in the body
Example
The politician's remarks served to inflame public opinion.
政治家の発言は公共の意見を煽る結果になった。
B2 adjective ɪnˈev.ɪ.tə.bəl

inevitable

避けられない
Meaning
Certain to happen; unavoidable.
Example
Death is an inevitable part of life.
死は人生の避けられない一部です。
C1 adjective /ˌaɪdiəˈlɪstɪk/

Idealistic

理想主義的
Meaning
pursuing high principles or ideals; unrealistically optimistic
Example
She has an idealistic view of changing the world.
彼女は世界を変えるという理想主義的な見方を持っています。
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。
B2 verb /ɪnˈdjuːs/

induce

誘発する
Meaning
to cause or persuade someone to do something; to bring about a result
Example
The doctor induced sleep with a mild sedative.
医師は軽い鎮静剤で睡眠を引き起こしました。
C1 verb /ɪnˈsɪnjueɪt/

insinuate

Meaning
To suggest or hint something indirectly and often unpleasantly.
Example
He insinuated that she had lied about her qualifications.
C1 noun /ˌɪntərˈdʒɛkʃən/

interjection

感嘆詞
Meaning
a word or phrase used to express sudden emotion or reaction, often standing alone
Example
Words like 'wow' and 'ouch' are common interjections in English.
'わお'や'痛っ'は英語でよく使われる感嘆詞です。
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。
C1 adjective /aɪˈreɪt/

irate

激怒した
Meaning
Extremely angry.
Example
The customer became irate after waiting for hours.
顧客は何時間も待った後、激怒しました。
C1 verb /ɪnˈvælɪdeɪt/

invalidate

無効にする
Meaning
To make something not valid or legally acceptable.
Example
The new evidence may invalidate the previous ruling.
新しい証拠が前の判決を無効にするかもしれません。
C1 noun /ˌɪnsəˈfɪʃənsi/

insufficiency

不足
Meaning
The state of not being enough or not being adequate.
Example
The project failed due to the insufficiency of funds.
プロジェクトは資金不足のため失敗しました。
A1 preposition /ɪn ˈfrʌnt əv/

in front of

〜の前に
Meaning
positioned before or ahead of something; facing or located at the forward side of a person or object
Example
She stood in front of the building.
彼女は建物の前に立っていた。
C1 adjective /ɪnˈsɒlvənt/

insolvent

破産
Meaning
unable to pay debts owed
Example
The insolvent firm could not meet its financial obligations.
破産した企業は財務義務を果たせなかった。