impolitic
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C2 adjective /ɪmˈpɑːlɪtɪk/

impolitic

無礼な
Meaning
Unwise or imprudent; not showing good judgment.
Example
It would be impolitic to criticize them openly.
彼らを公然と批判するのは無礼だろう。
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。
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。
C2 verb /ɪnˈdɛmnɪfaɪ/

indemnify

Meaning
to compensate someone for harm or loss; to secure against future damage or cost
Example
The insurance company agreed to indemnify the client for the damages.
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。
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 /ˈɪntərˌloʊpər/

interloper

干渉者
Meaning
A person who becomes involved in a situation or place where they are not wanted.
Example
He felt like an interloper at the private family gathering.
彼はプライベートな家族の集まりで干渉者のように感じた。
C2 adjective /ˌɪnkænˈdɛsənt/

incandescent

白熱
Meaning
emitting light as a result of being heated; extremely bright or passionate
Example
The incandescent lamp lit up the entire hall.
白熱灯はホール全体を照らしました。
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 adverb /ˌɪnəzˈmʌtʃ/

inasmuch

〜という点で
Meaning
To the extent that; considering that.
Example
Inasmuch as you are their teacher, you should guide them carefully.
あなたが彼らの教師である限り、彼らを慎重に指導するべきです。
C2 adjective /ˌɪnˈekspɜːrt/

inexpert

未熟な
Meaning
not skilled or experienced; lacking expertise
Example
The inexpert handling of the machine caused several mistakes.
機械の未熟な扱いがいくつかのミスを引き起こした。
C2 noun /ˌɪnədˈvɜːrtəns/

inadvertence

不注意
Meaning
Failure to pay attention; carelessness.
Example
The error happened through sheer inadvertence.
エラーは単なる不注意で発生しました。
C2 adjective /ɪnˈsɪpɪd/

insipid

味気ない
Meaning
lacking flavor, interest, or excitement; dull
Example
The soup was insipid and needed more seasoning.
スープは味気なく、もっと調味料が必要でした。
C2 adjective /ɪnˈvaɪələt/

inviolate

汚されていない
Meaning
free from violation, injury, or desecration; kept safe and untouched
Example
The ancient temple remained inviolate for centuries.
古代の寺院は何世紀にもわたって汚されることなく保たれました。
C2 verb /ˌɪn.trəˈmɪt/

intromit

挿入する
Meaning
To insert or introduce something into a place or body.
Example
The doctor carefully intromitted the instrument into the wound.
医者は慎重に器具を傷口に挿入しました。
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 /ɪnˈɡreɪʃiˌeɪt/

ingratiate

Meaning
To gain favor or approval by deliberate effort, often in a flattering way.
Example
She tried to ingratiate herself with her boss by complimenting him often.
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 noun /ˌɪntərˈlɒkjətər/

interlocutor

対話者
Meaning
a person who takes part in a conversation or dialogue
Example
She was a skilled interlocutor during the debate.
彼女は討論中に優れた対話者でした。
C2 adjective /ɪnˈɛksərəbl/

inexorable

避けられない
Meaning
Impossible to stop or prevent; relentless.
Example
The inexorable rise of technology is changing every aspect of life.
テクノロジーの避けられない上昇は、生活のすべての側面を変えています。
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。
C2 noun /ɪnˈtɛmpərəns/

intemperance

節度を欠くこと
Meaning
Lack of moderation or self-control, especially with drinking or eating.
Example
His intemperance in drinking ruined his health.
彼の飲酒の節度を欠くことが健康を害した。
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 /ɪnˈkwɪzɪtər/

inquisitor

尋問者
Meaning
A person who asks many questions, often in an official or harsh manner.
Example
The inquisitor demanded detailed answers from the witness.
尋問者は証人から詳細な回答を要求しました。
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。
C2 adjective /ˌɪntərˈniːsaɪn/

internecine

内部紛争
Meaning
Relating to conflict within a group, often causing mutual destruction.
Example
The internecine conflict weakened the organization from within.
内部紛争は組織を内部から弱体化させた
C2 noun /ˈaɪdlər/

idler

怠け者
Meaning
A person who avoids work or spends time lazily.
Example
He was known as an idler who wasted his days.
彼は自分の時間を無駄にするアイドラーとして知られていました。
C2 adjective /ˌɪn.ɪˈlʌk.tə.bəl/

ineluctable

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

inveterate

常習的な
Meaning
having a long-established habit, activity, or interest that is unlikely to change
Example
He is an inveterate reader who spends hours in the library every day.
彼は毎日数時間を図書館で過ごす常習的な読者です。
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。
C2 adjective /ɪnˈfɜːrnəl/

infernal

地獄の
Meaning
relating to hell; extremely troublesome or annoying
Example
The workers complained about the infernal noise from the construction site.
労働者たちは建設現場からの地獄のような騒音について文句を言った。
C2 noun /ɪmp/

imp

小さないたずら好きな悪魔
Meaning
a small mischievous devil or sprite; a playful troublemaker
Example
The child was acting like a little imp, hiding his toys everywhere.
その子供は小さなインプのように振る舞い、どこにでもおもちゃを隠していました。
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.
C2 adjective /ɪmˈpɔːrtʃənət/

importunate

しつこい
Meaning
Persistent to the point of annoyance or intrusion
Example
The importunate salesman kept calling despite repeated refusals.
しつこい販売員は、繰り返し拒否されても電話をかけ続けました。
C2 adjective /ˌɪnkoʊˈɜːrsəbl̩/

incoercible

強制できない
Meaning
Not capable of being forced, compelled, or restrained.
Example
Her incoercible spirit inspired others to fight for justice.
彼女の強制できない精神は他の人々に正義のために戦うようにインスパイアした。
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。
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 /ˌɪnkəmˈbʌstəbl/

incombustible

不燃
Meaning
Not capable of catching fire or burning.
Example
This material is incombustible and safe for construction.
この材料は燃えません、安全に建設に使用できます。
C2 adjective /ˌɪnkɒntrəˈvɜːtəbl/

incontrovertible

論争の余地がない
Meaning
impossible to deny or dispute; unquestionable
Example
The evidence was incontrovertible and proved his innocence.
その証拠は論争の余地がなく、彼の無罪を証明しました。
C2 adjective /ˌɪndɪˈvɜːrtɪbəl/

indivertible

Meaning
Not able to be turned aside or diverted.
Example
The judge's indivertible attention was on the case.
C2 noun /ˌɪn.ʌnˈdeɪ.ʃən/

inundation

洪水
Meaning
The act of flooding or overwhelming with water or things.
Example
The town suffered from a severe inundation after the heavy rains.
町は大雨後にひどい洪水に見舞われました。
C2 adjective /ˌɪndaɪˈdʒestəbəl/

Indigestible

消化不良な; 消化しにくい
Meaning
difficult or impossible to digest; hard to process in the stomach
Example
The old bread became hard and indigestible.
古いパンは硬くなり、消化不良になった。
C2 noun /ɪnˈkɒnstənsi/

inconstancy

不安定さ
Meaning
The quality of changing frequently or being unreliable.
Example
The inconstancy of the weather makes planning difficult.
天候の不安定さが計画を難しくします。
C2 adjective /ˌɪrɪˈkɒnsɪləbl/

irreconcilable

和解できない
Meaning
impossible to make compatible or bring into harmony; unable to resolve differences
Example
The couple separated due to irreconcilable differences.
そのカップルは和解できない違いのために別れました。
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 noun /ˌɪn.təˈvɛn.ʃə.nɪ.zəm/

interventionism

介入主義
Meaning
Government policy of active involvement in economic affairs.
Example
The central bank's interventionism helped stabilize inflation.
中央銀行の介入主義はインフレの安定に役立った。
C2 adjective/verb /ɪnˈkɑːrneɪt/

incarnate

具現化
Meaning
to embody or represent in human form; in flesh
Example
She is kindness incarnate.
彼女は親切さの具現化です。
C2 adjective /ˌaɪ.kə.nəˈklæs.tɪk/

iconoclastic

確立された信念、伝統、または価値観に対して攻撃的または拒絶的な特徴
Meaning
Characterized by attacking or rejecting cherished beliefs, traditions, or established values.
Example
Her iconoclastic views challenged the conventional wisdom of the industry.
彼女のアイコノクラスティックな見解は業界の従来の知恵に挑戦した。
C2 adjective /ɪˈnɪm.ɪ.tə.bəl/

inimitable

比類のない
Meaning
So good or unusual as to be impossible to copy; unique.
Example
His inimitable writing style made him a literary legend.
彼の比類のない筆致が彼を文学の伝説にした。
C2 noun /ˌɪndɛnˈteɪʃən/

indentation

インデント
Meaning
A space left at the beginning of a line of text; a notch or deep recess on a surface.
Example
The teacher asked the students to use proper indentation in their essays.
先生は学生にエッセイで適切なインデントを使用するように頼みました。
C2 noun /ɪnˈfriːkwəns/

infrequence

稀少性
Meaning
The state of occurring rarely or at long intervals.
Example
The infrequence of their meetings made it hard to maintain close ties.
彼らの会議の稀少性は、親密な関係を維持するのを難しくしていました。
C2 noun /ɪˌluːmɪˈnɑːti/

illuminati

イルミナティ
Meaning
a group of people claiming to have special enlightenment or secret knowledge, often linked to conspiracies
Example
Many conspiracy theories involve the Illuminati as a secret world-controlling group.
多くの陰謀論はイルミナティを世界を支配する秘密のグループとして扱っている。
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。
C2 adjective /ˌɪn.trəˈsɛl.jʊ.lər/

intracellular

細胞内
Meaning
Located or occurring within a cell.
Example
The drug works by targeting intracellular bacteria.
薬は細胞内の細菌をターゲットにして作用します。
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 verb /ˈɪmprɪkeɪt/

imprecate

呪う
Meaning
To utter a curse or invoke evil upon someone.
Example
The old woman imprecated her enemies with dark words.
その年老いた女性は暗い言葉で敵を呪いました。
C2 adjective /ˈɪnˌbrɛd/

inbred

生まれつき
Meaning
existing naturally in a person or animal; also related to reproduction within a limited community
Example
He has an inbred sense of loyalty.
彼には生まれつきの忠誠心があります。
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 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 /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。
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。
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。
C2 noun /ɪnˈhɪərəns/

inherence

内在性
Meaning
The state of being an essential or permanent part of something.
Example
The inherence of risk is part of every business venture.
リスクの内在性はすべてのビジネス冒険の一部です。
C2 adjective /ɪˈnɪmɪkəl/

inimical

敵対的 / 不利な
Meaning
tending to obstruct or harm; unfriendly or hostile
Example
The policy was inimical to the country's economic growth.
その政策は国の経済成長に不利だった。
C2 adjective /ɪnˈkɒntɪnənt/

incontinent

失禁
Meaning
lacking control over urination or defecation; lacking self-restraint
Example
The patient was incontinent after surgery.
手術後、患者は失禁していた。
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.
C2 adjective /ˌɪnɪˈsɛnʃəl/

inessential

本質的でない
Meaning
not necessary or important; not essential
Example
The report removes all inessential details to stay focused.
その報告書は焦点を保つために本質的でない詳細を削除している。
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。
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 noun /ˈɪɡ.nəˌmɪn.i/

ignominy

恥辱
Meaning
Public shame, disgrace, or dishonor.
Example
He lived the rest of his life in ignominy after the scandal.
スキャンダル後、彼は生涯を恥辱の中で過ごした。
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。
C2 adjective /ɪnˈvɪdiəs/

invidious

妬ましい
Meaning
likely to arouse resentment, envy, or anger in others
Example
The manager's invidious remarks created tension among the employees.
マネージャーの妬ましいコメントは、従業員の間に緊張を生み出しました。
C2 adjective /ˌaɪsəʊˈθɜːrməl/

isothermal

等温
Meaning
Having or maintaining equal or constant temperature.
Example
The experiment was conducted under isothermal conditions.
実験は等温条件で行われました。
C2 adjective /ɪmˈpruːdənt/

imprudent

不注意な
Meaning
Not showing care for the consequences of an action.
Example
It was imprudent to drive in such stormy weather.
こんな嵐の天気で運転するのは不注意だった。
C2 noun /ɪmˈpruː.dəns/

Imprudence

無分別; 不注意; 軽率
Meaning
the quality of being imprudent; lack of care for consequences; recklessness
Example
His financial imprudence led to bankruptcy within just two years.
彼の財務の無分別は、わずか2年で破産を招いた。
C2 verb ˈɪnʌndeɪt

inundate

洪水で満たす、処理すべき事柄や人々で誰かまたは何かを圧倒する
Meaning
To flood; overwhelm someone or something with things or people to be dealt with
Example
The company was inundated with requests after the advertisement.
広告の後、会社はリクエストで圧倒されました。
C2 noun /ɪˈreɪdiəns/

irradiance

放射輝度
Meaning
the quality of shining brightly; the intensity of light falling on a surface
Example
The irradiance of the sun at noon was overwhelming.
正午の太陽の放射輝度は圧倒的でした。
C2 adjective /ˌɪnfɪnɪˈtɛsɪməl/

infinitesimal

微細な
Meaning
Extremely small in size or amount; so tiny as to be almost negligible.
Example
The error was so infinitesimal that it didn’t affect the results.
そのエラーは非常に微細で、結果に影響を与えることはありませんでした。
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 /ˈɪn.tɪ.ɡreɪ.tɪv dɪˈpləʊ.mə.si/

integrative diplomacy

統合的外交
Meaning
A diplomatic approach that seeks to combine or coordinate different elements, interests, or parties into a unified whole.
Example
Integrative diplomacy strengthens alliances.
統合的外交は同盟を強化する。
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。
C2 adjective /ɪmˌpɜːrˈsweɪdəbl/

impersuadable

説得できない
Meaning
not able to be convinced or persuaded
Example
She remained impersuadable despite all our arguments.
彼女はすべての議論にもかかわらず説得できなかった。
C2 noun /ˈɪl.i.æd/

iliad

イリアス
Meaning
An ancient Greek epic poem attributed to Homer, describing the events of the Trojan War.
Example
Students studied the Iliad to understand Greek mythology and heroism.
学生たちはイリアスを学び、ギリシャ神話と英雄主義を理解しました。
C2 adjective /ˌɪndɪˈsɒljʊbl/

indissoluble

解消できない
Meaning
Unable to be destroyed, broken, or dissolved.
Example
Marriage was once considered an indissoluble bond.
結婚はかつて解消できない絆と見なされていました。
C2 verb /ɪnˈveɪɡəl/

inveigle

誘惑する
Meaning
To persuade someone to do something by deception or flattery.
Example
She inveigled him into signing the contract.
彼女は彼に契約書に署名させた。
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。
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 adjective /ɪnˈæpt/

Inapt

不適切; 不適当
Meaning
not suitable; inappropriate; unfit
Example
His comment was inapt for the formal meeting.
彼のコメントは正式な会議には不適切でした。
C2 adjective /ɪnˈdɛkərəs/

indecorous

不作法
Meaning
Not in keeping with good taste and propriety; improper.
Example
His indecorous behavior shocked the audience.
彼の不作法な振る舞いは観客を驚かせた。
C2 adjective /ɪnˈkɒrɪdʒəbəl/

incorrigible

訂正不可能な
Meaning
incapable of being corrected, improved, or reformed
Example
He is an incorrigible optimist who never loses hope.
彼は決して希望を失わない訂正不可能な楽観主義者です。
C2 noun /ɪmˌprɒb.əˈbɪl.ə.ti/

Improbability

不確実性
Meaning
the quality or state of being improbable; unlikely to be true or to happen
Example
The improbability of winning the lottery twice didn't stop her from buying tickets.
ロトで二回連続で当選する可能性の低さは、彼女がチケットを買うのを止めませんでした。
C2 adverb /ɪnˈdjuːbɪtəbli/

indubitably

疑いなく
Meaning
Without a doubt; certainly.
Example
She is indubitably the best candidate for the job.
彼女は疑いなくその仕事の最良の候補者です。
C2 adjective /ˌɪnkəmˈprɛsəbl/

incompressible

圧縮不可能
Meaning
Not able to be pressed or squeezed into a smaller space.
Example
Liquids are generally considered incompressible.
液体は通常、圧縮不可能と見なされます。
C2 noun /ɪˈrʌp.ʃən/

Irruption

突然の暴力的な侵入; 侵略または襲撃; 突然の噴出または噴火
Meaning
a sudden violent entry; an invasion or raid; a sudden outburst or eruption
Example
The army's irruption into enemy territory caught the opposing forces completely off guard.
軍隊の敵領土へのイラプションは、相手の力を完全に不意を突いた。
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 noun /ɪnˈsaɪzər/

incisor

切歯
Meaning
a narrow-edged tooth at the front of the mouth, adapted for cutting
Example
The dentist noted that his upper left incisor was chipped.
歯科医は彼の上の左側の切歯が欠けていることに気づきました。
C2 verb /ɪnˈdʒɛst/

ingest

摂取する
Meaning
To take food, drink, or another substance into the body, usually by swallowing.
Example
The patient must ingest the medicine with water.
患者は水と一緒に薬を摂取する必要があります。
C2 noun /ˈaɪ.lət/

islet

小島
Meaning
A very small island.
Example
The fishermen rested on a tiny islet before continuing their journey.
漁師たちは旅を続ける前に小さな島で休憩しました。
C2 adjective /ˌɪməˈmɔːriəl/

immemorial

不朽の
Meaning
Extending back beyond memory or record; ancient.
Example
The tradition has been followed since time immemorial.
その伝統は不朽の時代から受け継がれてきた。
C2 adjective /ɪnˈkɒnstənt/

inconstant

不安定な
Meaning
frequently changing; not consistent or dependable
Example
His inconstant moods made it difficult to work with him.
彼の不安定な気分は彼と仕事をするのを難しくした。
C2 verb /ɪˈluːmɪn/

illumine

照らす
Meaning
to light up or make clear
Example
The rising sun illumined the mountain peaks.
昇る太陽が山頂を照らした。
C2 adjective ɪˈnɛfəbl

ineffable

言葉で表現できない
Meaning
Too great or extreme to be expressed or described in words.
Example
The beauty of the landscape was ineffable.
その景色の美しさは言葉で表現できなかった。
C2 adjective /ˌɪnsəˈluːbriəs/

insalubrious

不健康
Meaning
Unhealthy or not conducive to well-being.
Example
They moved out of the insalubrious neighborhood for the sake of their health.
彼らは健康のために不健康な地域から引っ越しました
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。
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。
C2 adjective /ɪnˈeɪliənəbl/

inalienable

譲渡不可能
Meaning
Unable to be taken away or transferred; absolute and permanent.
Example
Freedom of speech is an inalienable right.
言論の自由は譲渡不可能な権利です。
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 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 /ˌɪrɪˈfrændʒɪbəl/

irrefrangible

侵害できない
Meaning
Not to be broken, violated, or infringed
Example
The constitution guarantees certain irrefrangible rights to every citizen.
憲法はすべての市民にいくつかの侵害できない権利を保証します。
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。
C2 noun /ˌɪmpjuˈteɪʃən/

imputation

非難
Meaning
an accusation or attribution of blame
Example
The politician denied the imputation of corruption.
政治家は腐敗の非難を否定した。
C2 adjective /ˌɪm.pəˈfɛk.tə.bəl/

imperfectible

インパーフェクティブル
Meaning
Incapable of being made perfect or complete.
Example
Some human qualities are considered imperfectible.
いくつかの人間の資質は、完璧にはならないと見なされます。
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。
C2 noun /ɪmˈprɑːvɪdəns/

improvidence

不注意
Meaning
Lack of foresight or care for future needs.
Example
His improvidence led to financial difficulties.
彼の不注意が彼を財政的な困難に追い込んだ。
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 noun /ɪnˈvaɪtər/

invitor

招待者
Meaning
a person who invites someone to an event, meeting, or place
Example
The invitor greeted all the guests warmly at the entrance.
招待者は入口で客を温かく迎えた。
C2 adjective /ɪnˈvʌlnərəbl/

invulnerable

無敵
Meaning
Impossible to harm, damage, or defeat.
Example
The fortress was thought to be invulnerable to attack.
その要塞は攻撃に対して無敵だと考えられていた。
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。
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。