investiture
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C2 noun /ɪnˈvɛstɪtʃər/

investiture

任命式
Meaning
the formal ceremony of conferring authority, rank, or office
Example
The king held an investiture ceremony for the new knight.
王は新しい騎士のために任命式を開催しました。
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。
C1 noun /aɪˈdiː.ə.lɪ.zəm/

Idealism

理想主義
Meaning
the pursuit of high principles and noble goals; unrealistic pursuit of perfection
Example
His youthful idealism motivated him to join various social justice movements.
彼の若い理想主義は、彼を様々な社会正義運動に参加させる原動力となった。
C1 verb /ɪnˈterəˌɡeɪt/

interrogate

尋問する
Meaning
to ask someone questions in a thorough and formal way; to question intensively
Example
The police interrogated the suspect for hours.
警察は容疑者を何時間も尋問した。
C2 noun /ˌɪkθiˈɒlədʒi/

ichthyology

魚類学
Meaning
The branch of zoology that deals with fish.
Example
He pursued a degree in ichthyology at the university.
彼は大学で魚類学の学位を取得した。
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。
B2 adjective /ɪnˈtriːɡɪŋ/

intriguing

非常に興味深く、異常な; 好奇心を引き起こす
Meaning
very interesting and unusual; arousing curiosity
Example
The movie has an intriguing plot that keeps the audience hooked.
その映画は観客を引き付ける非常に興味深いプロットを持っています。
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。
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 verb /ˈɪntərˌdɪkt/

interdict

禁じる
Meaning
to prohibit or forbid something by authoritative order, often by law or decree
Example
The court moved to interdict the sale of the illegal goods.
裁判所は違法な商品の販売を禁じることを決定しました。
C2 noun (compound/erroneous entry) /ɪnˈɛksərəbl ɑːrmi/

inexorableinexorablearmy

止められない軍隊
Meaning
This appears to be a corrupted or concatenated form; interpreted as 'inexorable army' — an unstoppable or relentless force.
Example
The rebels feared the inexorable army approaching their stronghold.
反乱軍は自分たちの砦に近づいてくる止められない軍隊を恐れていた。
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 noun /ˌɪn.trəˈvɜːr.ʒən/

introversion

内向
Meaning
The tendency to be inward-looking and shy, preferring solitary activities.
Example
Her introversion made it difficult for her to enjoy large parties.
彼女の内向的な性格は、大きなパーティーを楽しむのを難しくした。
B2 noun /ˌɪm.ɪˈteɪ.ʃən/

Imitation

模倣; コピー; レプリカ
Meaning
the action of using someone or something as a model; a copy of something original
Example
His imitation of the famous actor was so good that everyone burst into laughter.
彼の有名な俳優のイミテーションはとても上手で、みんなが笑い出しました。
C1 adjective /ˌɪnɪkˈsplɪkəbl/

inexplicable

説明できない
Meaning
Impossible to explain or understand.
Example
The sudden disappearance of the file was inexplicable.
ファイルの突然の消失は説明できなかった。
C2 adjective /ɪnˈɡreɪʃiˌeɪtɪŋ/

ingratiating

お世辞を言う
Meaning
Charming or flattering in a way intended to gain favor.
Example
His ingratiating smile made everyone trust him quickly.
彼のお世辞を言う笑顔は、すべての人々に彼を素早く信頼させた。
C2 noun /ɪˈrɛvərəns/

irreverence

不敬
Meaning
a lack of respect for people or things that are generally taken seriously
Example
His jokes about religion showed irreverence to the sacred traditions.
宗教についての彼の冗談は、神聖な伝統に対する不敬を示していました。
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 noun /ɪnˈtræn.sɪ.dʒəns/

intransigence

不屈
Meaning
Refusal to change one's views or to agree about something.
Example
The negotiations failed due to the intransigence of both parties.
両者の不屈の姿勢のために交渉は失敗した。
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。
B1 noun ˌɪndɪˈpendəns

independence

独立
Meaning
The fact or state of being independent; freedom from outside control; not being subject to another's authority.
Example
Independence inspired the movement.
独立は運動を刺激した。
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。
C2 verb /ɜːrk/

irk

苛立たせる
Meaning
to annoy or irritate someone
Example
It irks me when people are late without calling.
人々が電話をかけずに遅れると、私はイライラします。
A1 preposition/adverb/adjective/noun /ˌɪnˈsaɪd/

inside

幸せ
Meaning
Situated within something; the inner part of something.
Example
She waited inside the house until the rain stopped.
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ませんでした。
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。
C1 adjective ˈɪn.lənd

Inland

内陸
Meaning
Situated in the interior of a country; away from the coast.
Example
Inland transport boosts local trade.
内陸輸送は地元の貿易を促進します。
C2 noun /ɪnˈsɪɡniə/

insignia

徽章
Meaning
A badge or symbol that shows rank, position, or membership.
Example
The soldier proudly wore the insignia of his regiment.
兵士は誇らしげに自分の連隊の徽章を身に着けていました。
C1 noun /ɪnˈfjuːʒən/

infusion

注入
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.
彼女はカモミールティーの落ち着く注入を準備しました。
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 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。
A2 noun /ˈɪntəvjuː/

interview

面接
Meaning
A meeting of people face to face, especially for consultation.
Example
The interview was conducted in a calm and professional manner.
面接は落ち着いたプロフェッショナルな方法で行われました。
B2 verb /ɪnˈʃʊər/

insure

保険をかける
Meaning
to provide insurance; to make certain
Example
I need to insure my new car.
私は新しい車を保険に入れる必要があります。
C2 adjective /ˈɪm.pi.əs/

Impious

不敬な; 冒涜的
Meaning
irreligious; lacking reverence for religion; blasphemous
Example
The impious act shocked the religious community.
不敬な行為は宗教コミュニティを驚かせました。
B2 noun ˌɪn.əˈveɪ.ʃən

innovation

革新
Meaning
The action or process of innovating; a new method, idea, product, etc.
Example
Innovation drives solutions to global challenges.
革新は世界的な課題への解決策を促進します。
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 /ɪnˈkrɪmɪˌneɪt/

incriminate

有罪にする
Meaning
to make someone appear guilty of a crime or wrongdoing
Example
The new evidence could incriminate the suspect in the robbery case.
新しい証拠がロビー事件の容疑者を有罪にする可能性があります。
B1 verb /ɪnˈvɛnt/

invent

発明する
Meaning
to create or design something that has not existed before
Example
Thomas Edison invented the electric bulb.
トーマス・エジソンは電球を発明しました。
C2 adjective /ˌɪnɪkˈstɛnsəbl/

inextensible

伸縮不可
Meaning
Not capable of being stretched or extended.
Example
This rope is made of an inextensible material.
このロープは伸縮不可の材料でできています。
B2 noun /ˈaɪ.dəl/

Idol

偶像; 崇拝される人物
Meaning
an image or representation of a god used as an object of worship; a person who is greatly admired
Example
The singer became a teenage idol after her hit song topped the charts worldwide.
その歌手はヒットソングが世界中のチャートで1位に達した後、ティーンエイジャーのアイドルとなった。
A2 verb /ˌɪntrəˈduːs/

introduce

紹介する
Meaning
to present someone; to bring in for the first time
Example
Let me introduce you to my friend.
友達を紹介させてください。
C2 adjective /ˌɪnˌɑːpərˈtuːn/

inopportune

タイミングが悪い瞬間
Meaning
Happening at a bad or inconvenient time.
Example
His call came at the most inopportune moment.
彼の電話は最もタイミングが悪い瞬間にかかってきた。
B2 adjective /ˌɪnəˈproʊpriət/

inappropriate

不適切
Meaning
not suitable or proper in the circumstances
Example
It was inappropriate to talk loudly in the library.
図書館で大声で話すのは不適切でした。
C1 adjective /ɪnˈkwɪzɪtɪv/

inquisitive

好奇心旺盛な
Meaning
Curious or eager to learn and ask questions.
Example
The inquisitive child asked endless questions about the stars.
好奇心旺盛な子供は星について無限に質問をしました。
B1 noun /ˈɪnsɪdənt/

incident

インシデント
Meaning
an event or occurrence, often unpleasant or unusual
Example
The police quickly responded to the incident in the park.
警察は公園でのインシデントに迅速に対応しました。
C2 noun /ˌɪməʊˈbɪləti/

immobility

不動
Meaning
The state of being unable to move.
Example
After the accident, she suffered from immobility in her legs.
事故の後、彼女は足の不動に苦しみました。
C1 adjective /ˌɪn.ɪˈfɛk.tʃu.əl/

ineffectual

効果がない
Meaning
Not producing any or the desired effect; lacking the ability or qualities to achieve a purpose.
Example
The manager’s ineffectual leadership caused the team to lose motivation.
マネージャーの効果がないリーダーシップは、チームがモチベーションを失う原因となった。
B2 noun /aɪˌdɛntɪfɪˈkeɪʃən/

identification

身分証明
Meaning
the process of recognizing or proving who or what someone or something is
Example
You need proper identification to enter the building.
ビルに入るには適切な身分証明が必要です。
C2 adverb /ˈɪntʃmiːl/

inchmeal

少しずつ
Meaning
Gradually, little by little.
Example
The old castle fell inchmeal into ruin.
その古い城は少しずつ廃墟になった。
C1 noun /ɪnˈsek.tɪ.saɪd/

Insecticide

殺虫剤
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.
農夫は作物を有害な虫から守るために殺虫剤を噴霧しました。
B2 adjective /ɪnˈtɛns/

intense

強烈
Meaning
Of extreme force, degree, or strength.
Example
She felt intense pain after the accident.
事故後、彼女は強烈な痛みを感じました。
B1 adjective /ɪnkəˈrɛkt/

incorrect

間違い
Meaning
not correct or accurate
Example
The information you provided was incorrect.
あなたが提供した情報は間違っていました。
C2 noun /ˌɪdiəˈsɪŋkrəsi/

idiosyncrasy

特異性
Meaning
A distinctive or peculiar characteristic, habit, or mannerism unique to an individual.
Example
One of her idiosyncrasies was humming while working.
彼女の一つの特異性は、仕事中に口ずさむことでした。
B2 verb ˈɪmplɪment

implement

実施する
Meaning
To put a decision or plan into effect; to execute or apply.
Example
Implementing educational policies is essential for progress.
教育政策を実施することは進歩にとって重要です。
B2 adverb /aɪˈrɒnɪkli/

ironically

皮肉にも
Meaning
in a way that is contrary to what is expected or intended
Example
Ironically, the fire station burned down.
皮肉にも、消防署が焼け落ちた。
C2 noun /aɪˈdɒlətri/

idolatry

偶像崇拝
Meaning
The worship of idols or extreme admiration for someone or something.
Example
The priest condemned the idolatry practiced in the village.
司祭は村で行われている偶像崇拝を非難した。
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。
B2 verb /ˌɪntərˈfɪər/

interfere

幸せ
Meaning
to become involved in something that is not your concern; to hinder or obstruct
Example
Parents should not interfere in their children’s personal choices.
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ませんでした。
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 noun /ɪnˈsɜːrdʒəns/

insurgence

反乱
Meaning
An act of rebellion or uprising against authority.
Example
The government struggled to contain the growing insurgence.
政府は増大する反乱を抑制するのに苦労した。
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。
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。
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 /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 /ɪnˈsuːsiənt/

insouciant

無頓着
Meaning
Showing a casual lack of concern; carefree.
Example
He gave an insouciant shrug and walked away.
彼は無頓着に肩をすくめて、歩き去った。
C1 adjective /ɪnˈvɪnsəbl/

invincible

無敵
Meaning
too powerful to be defeated or overcome
Example
The team seemed invincible after winning ten matches in a row.
そのチームは10試合連続で勝利した後、無敵に見えた。
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。
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。
C2 verb /ɪnˈsteɪt/

instate

任命する
Meaning
To set up in position, office, or authority.
Example
The board decided to instate her as the new director.
取締役会は彼女を新しいディレクターにインステイトすることを決定しました。
C1 verb /ɪnˈklaɪn/

incline

傾く
Meaning
to feel willing or favorably disposed toward something; to bend or tilt
Example
She is inclined to agree with the proposal.
彼女は提案に賛成する傾向があります。
C2 adjective /ɪˈmɪsəbl/

immiscible

不混和
Meaning
Describes liquids that do not mix together.
Example
Oil and water are immiscible liquids.
油と水は不混和の液体です。
B2 noun ˌɪm.plɪˈkeɪ.ʃən

implication

含意
Meaning
A conclusion that can be drawn from something although it is not explicitly stated; a likely consequence.
Example
The implication of climate change is severe.
気候変動の含意は深刻です。
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。
C2 noun /ˌɪlɪbəˈræləti/

illiberality

不寛容
Meaning
The quality of being illiberal; lack of tolerance or generosity.
Example
The illiberality of the new laws alarmed the citizens.
新しい法律の不寛容が市民を驚かせました。
B1 noun /ɪnˌvɛs.tɪˈɡeɪ.ʃən/

investigation

調査
Meaning
the process of inquiring into or examining something carefully to find the truth
Example
The investigation revealed new evidence about the fraud.
調査は詐欺に関する新しい証拠を明らかにしました。
C1 adjective /ɪmˈpɑːrʃəl/

Impartial

公正; 中立的
Meaning
treating all sides fairly; unbiased; neutral
Example
A good judge must remain impartial throughout the trial.
優れた裁判官は裁判中に公正を保たなければなりません。
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。
C2 adjective /ɪˈnjʊərd/

inured

慣れた
Meaning
Accustomed to something, especially something unpleasant.
Example
After years of hardship, she was inured to suffering.
長年の苦しみの後、彼女は苦しみに慣れていた。
C2 noun /ɪˈnænɪti/

inanity

馬鹿げたこと, 空虚
Meaning
a nonsensical remark or action; silliness; emptiness
Example
The speech was full of inanities that bored the audience.
スピーチは聴衆を退屈させる馬鹿げたことだらけだった。
B1 verb /ˈɪndɪkeɪt/

indicate

示す
Meaning
to point out; to show or suggest; to be a sign of
Example
The red light indicates that you should stop.
赤い信号は停止すべきことを示しています。
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 /ˌɪn.səˌbɔːr.dɪˈneɪ.ʃən/

insubordination

反抗
Meaning
Defiance of authority; refusal to obey orders.
Example
The soldier was punished for insubordination during the mission.
その兵士はミッション中の反抗で罰せられました。
C2 verb /ɪnˈdɒktrɪˌneɪt/

indoctrinate

教義を押し付ける
Meaning
To teach someone to fully accept a set of beliefs or ideas without question.
Example
The regime tried to indoctrinate the youth with propaganda.
その政権は宣伝を通じて若者を洗脳しようとした。
C1 adjective /ˌɪntəˈrɑːɡətɪv/

interrogative

疑問の
Meaning
Relating to or conveying a question; in grammar, used to form questions.
Example
She raised an interrogative eyebrow when she heard the news.
彼女はそのニュースを聞いて疑問のまなざしを向けました。
C2 adjective /ɪˈrɛfrəɡəbəl/

irrefragable

反論できない
Meaning
Impossible to refute, deny, or break
Example
The lawyer presented irrefragable evidence that proved his client’s innocence.
弁護士は彼のクライアントの無実を証明する反論できない証拠を提示しました。
C1 noun /ɪˈmɜː.ʃən/

immersion

没入
Meaning
Complete engagement in an environment or experience.
Example
Immersion in VR games makes users feel like they are inside the virtual world.
VRゲームへの没入は、ユーザーが仮想世界にいるように感じさせます。
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。
A2 adverb /ɪnˈstɛd/

instead

代わりに
Meaning
As an alternative or substitute.
Example
She didn’t buy the dress; instead, she chose a pair of shoes.
彼女はドレスを買わなかった。代わりに、彼女は靴を選んだ。
B2 noun /ɪnˈsen.tɪv/

Incentive

インセンティブ; 刺激
Meaning
a thing that motivates or encourages someone to do something; a reward or penalty that influences behavior
Example
The company offered a cash incentive to employees who exceeded their sales targets.
その会社は売上目標を達成した従業員に現金インセンティブを提供しました。
B1 adverb /ɪnˈkriːsɪŋli/

increasingly

ますます
Meaning
more and more over time
Example
People are increasingly concerned about climate change.
人々は気候変動についてますます懸念しています。
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。
B2 verb /ˈaɪ.sə.leɪt/

isolate

隔離する
Meaning
To separate something or someone from others.
Example
Doctors tried to isolate the patient to prevent the spread of infection.
医師たちは感染の拡大を防ぐために患者を隔離しようとしました。
B2 adjective + noun aɪˈdiːəl ɪnˈvaɪrənmənt

ideal environment

理想的な環境
Meaning
Perfect or most suitable conditions for growth or development
Example
Winter creates an ideal environment for vegetable growth.
冬は野菜の成長に理想的な環境を作り出します。
C1 verb /ɪmˈpɛl/

impel

Meaning
to drive, force, or urge someone to do something
Example
Her curiosity impelled her to open the mysterious box.
C2 adjective /ɪˈmɒdɪst/

immodest

傲慢 / 不適切
Meaning
lacking humility or decency; excessively proud or improper
Example
His immodest remarks offended the audience.
彼の傲慢な発言は観客を不快にさせた。
C2 verb /ɪnˈtɜːrpəˌleɪt/

interpolate

挿入する
Meaning
To insert something, often words, into a text or conversation; to estimate values between known data points.
Example
The editor interpolated a missing paragraph into the manuscript.
編集者は原稿に欠落した段落を挿入した。
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。
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 noun /ˈɪdɪət/

idiot

バカ
Meaning
a person who acts in a way that is considered very stupid or foolish
Example
He acted like an idiot at the party last night.
彼は昨晩のパーティーでイディオットのように振る舞った。
C2 noun /ˌɪnsəˈrɛkʃən/

insurrection

反乱
Meaning
A violent uprising against an authority or government.
Example
The army was called in to suppress the insurrection.
軍隊は反乱を鎮圧するために呼ばれました。
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 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。
C2 verb /ɪmˈpɛnd/

impend

迫る
Meaning
to be about to happen; to loom threateningly
Example
Dark clouds suggested that a storm was impeding.
暗い雲が嵐が迫っていることを示唆していた。
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。
B1 adjective /ɪnˈfɔːrməl/

Informal

非公式; リラックス; カジュアル
Meaning
relaxed and friendly; not official or ceremonial; casual
Example
The meeting was informal and relaxed.
会議は非公式でリラックスしていました。
C1 adjective /ˌɪnhɒˈspɪtəbl/

inhospitable

住みにくい
Meaning
Harsh and difficult to live in; unfriendly or unwelcoming to guests.
Example
The desert is an inhospitable environment for most plants.
砂漠はほとんどの植物にとって住みにくい環境です。
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 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。
C2 adjective /ɪˈlɪbərəl/

illiberal

非リベラル
Meaning
Opposed to liberal principles; restricting freedom of thought or behavior.
Example
The government was criticized for its illiberal policies.
政府はその非リベラルな政策について批判された。
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。
C2 adjective /ɪˈnɪkwɪtəs/

iniquitous

不正義
Meaning
grossly unfair and morally wrong
Example
Slavery was one of the most iniquitous practices in history.
奴隷制は歴史上最も不正義な行為の一つでした。
C2 noun /ˌɪmprɪˈmɑːtər/

imprimatur

承認
Meaning
An official license or approval, especially to publish a book.
Example
The book was released with the official imprimatur of the church.
その本は教会の正式な承認を得て出版されました。
C2 noun /aɪər/

ire

怒り, 激怒
Meaning
intense anger or rage
Example
The new policy provoked the ire of the employees.
新しい政策は従業員の怒りを引き起こした。
C1 adjective ɪmˈpɛkəbl

impeccable

完璧な
Meaning
In accordance with the highest standards; faultless.
Example
His impeccable taste in fashion was admired by all his peers.
彼の完璧なファッションセンスは、すべての同僚に賞賛されました。
B2 noun ˌɪntəˈlektʃuəlz

intellectuals

知識人
Meaning
People possessing a highly developed intellect; scholars or academics.
Example
Intellectuals protested against the dominance.
知識人は支配に反対した。
C1 noun /ɪnˈdaɪtmənt/

indictment

起訴状
Meaning
a formal charge or accusation of a serious crime
Example
The indictment accused the company of multiple violations.
起訴状は、会社に対する複数の違反を告発しました。
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。
C2 noun /ɪmˈpʌlʃən/

impulsion

Meaning
a strong urge or drive to act; the act of impelling
Example
His impulsion to travel made him leave his job suddenly.
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。
C2 noun /ˈaɪ.kɒn/

ikon

宗教的な画像やシンボル
Meaning
A religious image or symbol, especially in the Eastern Orthodox Church.
Example
The church displayed a beautifully painted ikon of the Virgin Mary.
教会は美しく描かれた聖母マリアのアイコンを展示しました。
C2 adjective/noun /ɪnˈkɑːrnədiːn/

incarnadine

深紅
Meaning
a bright crimson or pinkish-red color
Example
The sky turned incarnadine at sunset.
太陽が沈むと空は深紅色に変わった。
C1 adjective ˌɪn.təˈmɪt.ənt

intermittent

断続的
Meaning
Happening irregularly, not continuously.
Example
The rain was intermittent throughout the day.
雨は一日中断続的でした。