infusion
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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 /ɪnˈveɪsɪv/

invasive

侵襲的
Meaning
Tending to spread harmfully, intruding aggressively, or encroaching beyond proper boundaries.
Example
The doctor explained that the procedure was minimally invasive.
医者は、その手順が最小限の侵襲的であることを説明しました。
C1 adjective /ɪmˈpæʃənd/

impassioned

情熱的な
Meaning
Filled with or showing great emotion.
Example
She gave an impassioned speech about human rights.
彼女は人権について情熱的なスピーチを行いました。
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。
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 adjective /ˌɪnədˈmɪsəbl̩/

inadmissible

受け入れられない
Meaning
Not allowed, especially as evidence in a court of law.
Example
The judge ruled the evidence inadmissible.
裁判官は証拠を受け入れられないと判断しました。
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 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 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 adjective /ˌɪnˌkɒnsɪˈkwɛnʃəl/

inconsequential

重要でない
Meaning
Not important or significant; too small to matter.
Example
The mistake was minor and inconsequential.
その間違いは小さく、重要ではありませんでした。
C1 adjective /ˌɪnstənˈteɪniəs/

instantaneous

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

impairment

損傷、障害
Meaning
The state of being damaged or weakened; a disability or handicap.
Example
Hearing impairment can be caused by long-term exposure to loud noise.
聴力障害は長期間の大きな音への曝露によって引き起こされる可能性があります。
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。
C1 adjective /ɪnˈdiːsənt/

indecent

不品な
Meaning
not conforming to accepted standards of behavior or morality; improper or offensive
Example
He was warned for making an indecent remark during the meeting.
彼は不品な発言で注意された。
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。
C1 noun /ɪmˈpɛd.ɪ.mənt/

impediment

障害
Meaning
A hindrance or obstruction in doing something; something that prevents progress.
Example
Lack of funds is a major impediment to the project.
資金不足はプロジェクトの大きな障害です。
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 adjective /ɪnˈhɛrənt/

inherent

固有の
Meaning
Existing in something as a natural, permanent, or essential quality.
Example
There are inherent risks in extreme sports.
エクストリームスポーツには固有のリスクが存在する。
C1 verb /ɪˈnɔːɡjʊreɪt/

inaugurate

Meaning
To formally begin or introduce something, especially with a ceremony.
Example
The mayor will inaugurate the new bridge tomorrow.
C1 noun ˌɪnfrəˈstrʌktʃərəl dɪˈveləpmənt

infrastructural development

インフラ整備
Meaning
The process of building and improving the basic physical and organizational structures and facilities needed for the operation of a society or enterprise.
Example
Infrastructural development is necessary for efficient recycling.
インフラストラクチャー開発は効率的なリサイクルに必要です。
C1 noun ˌɪntədɪˈpɛndənsi

interdependency

相互依存
Meaning
The dependence of two or more people or things on each other.
Example
The interdependency of the countries led to greater cooperation.
国々の相互依存は、より大きな協力を生み出しました。
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 ɪnˌɛv.ɪ.təˈbɪl.ɪ.ti

inevitability

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

insensible

無意識
Meaning
Unconscious; unaware of or indifferent to something.
Example
He was insensible to the cold as he lay in the snow.
彼は雪の中で横たわっているとき、寒さに無意識でした。
C1 noun /ˈɪrɪtənt/

irritant

刺激物
Meaning
something that causes irritation or discomfort
Example
Dust is a common irritant for people with allergies.
ほこりはアレルギーを持つ人々にとって一般的な刺激物です。
C1 adjective /ɪnˈsʌf.ər.ə.bəl/

insufferable

耐え難い
Meaning
Too extreme to bear; intolerable.
Example
The heat during the summer was insufferable.
夏の暑さは耐え難かった。
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。
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 ɪnˌten.sɪ.fɪˈkeɪ.ʃən

intensification

強化
Meaning
The process of becoming or making something more intense or extreme.
Example
The intensification of climate change requires urgent action.
気候変動の強化は緊急の行動を必要とします。
C1 adjective ɪˈluː.sər.i

illusory

幻の
Meaning
Based on illusion; not real although seeming to be.
Example
His sense of security was entirely illusory.
彼の安全感は完全に幻のものだった。
C1 noun ˌɪn.ɪˈfɪʃ.ən.si

inefficiency

非効率
Meaning
The state or quality of not achieving maximum productivity; failure to make the best use of time or resources.
Example
Government inefficiency leads to slow project completion.
政府の非効率性がプロジェクトの完了を遅らせる。
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 noun /ˌaɪ.diˈɒl.ə.dʒi/

ideology

イデオロギー
Meaning
A system of ideas and ideals, especially one that forms the basis of economic or political theory and policy.
Example
Democracy is based on the ideology of freedom and equality.
民主主義は自由と平等のイデオロギーに基づいています。
C1 adjective /ɪˈledʒ.ə.bəl/

illegible

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

Impostor

詐欺師; 偽者
Meaning
a person who pretends to be someone else in order to deceive others; a fraud
Example
The impostor convinced everyone he was a doctor until his fake credentials were discovered.
詐欺師は医者だとみんなを納得させましたが、彼の偽の資格が発覚するまでそれが続きました。
C1 verb /ɪɡˈnaɪt/

ignite

点火する
Meaning
To catch fire or cause to catch fire; to start or arouse.
Example
The sparks ignited the dry leaves in seconds.
火花が数秒で乾燥した葉に火をつけた。
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 /ɪnˈsɪdiəs/

insidious

陰険な
Meaning
Proceeding in a gradual, subtle way but with harmful effects.
Example
The insidious spread of misinformation can damage trust.
誤った情報の陰険な広がりは信頼を傷つける可能性がある。
C1 noun ˌɪm.pʌlˈsɪv.ɪ.ti

impulsivity

衝動性
Meaning
The tendency to act quickly and without thought or care; lack of self-control.
Example
His impulsivity led him to make reckless choices.
彼の衝動性は、無謀な選択をさせた。
C1 noun /ˌɪnɪkˈspɪəriəns/

inexperience

未経験
Meaning
Lack of knowledge or skill in a particular activity or field.
Example
His inexperience in handling negotiations was evident.
交渉における彼の未経験は明らかでした。
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 /ˈɪnstɪˌɡeɪtər/

instigator

扇動者
Meaning
A person who brings about or initiates something, usually something bad.
Example
The police identified him as the instigator of the violence.
警察は彼を暴力の扇動者として特定しました。
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 /ˌɪn.trəˈspek.ʃən/

introspection

内省
Meaning
The examination or observation of one's own mental and emotional processes; self-reflection.
Example
Through introspection, she gained insight into her emotions.
内省を通じて、彼女は自分の感情に対する深い洞察を得ました。
C1 adjective /ɪnˈstrʌktɪv/

instructive

教育的
Meaning
useful and informative; providing knowledge or instruction
Example
The lecture was highly instructive and engaging.
その講義は非常に教育的で魅力的でした。
C1 verb /ˈɪnsjuleɪt/

insulate

Meaning
To protect something by covering it, especially to prevent heat, sound, or electricity from escaping or entering.
Example
The house was insulated to reduce heating costs.
C1 verb /ˈɪnfɪltreɪt/

infiltrate

浸透
Meaning
to secretly enter or gain access to a place or group
Example
The spies managed to infiltrate the enemy base.
スパイたちは敵基地に infiltrate できた。
C1 adjective /ɪmˈprɒbəbl/

improbable

あり得ない
Meaning
Not likely to be true or to happen.
Example
It seems improbable that he will arrive on time.
彼が時間通りに到着するのはあり得ないようだ。
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 adjective /ɪˈmjuː.tə.bəl/

immutable

不変の
Meaning
Unchangeable, permanent, or fixed
Example
The laws of physics are considered immutable.
物理法則は不変と見なされます。
C1 noun /ˌɪntərˈmiːdiˌɛri/

intermediary

仲介者
Meaning
A person who acts as a link between people in order to try to bring about an agreement; a mediator.
Example
The diplomat served as an intermediary between the two conflicting nations.
外交官は二つの対立する国々の間で仲介者として機能した。
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 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 verb /ɪnˈfrɪndʒ/

infringe

侵害する
Meaning
To actively break the terms of a law, agreement, or right.
Example
Copying this software without permission will infringe copyright laws.
許可なくこのソフトウェアをコピーすると著作権法を侵害することになります。
C1 verb /aɪˈdiː.ə.laɪz/

idealize

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

indispensable support

欠かせないサポート
Meaning
Essential assistance that cannot be done without; absolutely necessary help.
Example
Volunteers provide indispensable support to communities.
ボランティアはコミュニティに欠かせないサポートを提供しています。
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 /ɪnˈɛk.wɪ.ti/

inequity

不平等
Meaning
Lack of fairness or justice; unequal distribution or treatment.
Example
Social inequity continues to be a global issue.
社会的不平等は依然としてグローバルな問題です。
C1 verb /ɪˈmɔːrtəlaɪz/

immortalize

不朽の
Meaning
to preserve the memory of someone or something forever
Example
The statue was built to immortalize the hero’s sacrifice.
その像は、英雄の犠牲を永遠にするために建てられました。
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。
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 noun /ˌɪrɪˌspɒnsəˈbɪləti/

irresponsibility

無責任
Meaning
lack of responsibility or accountability; failure to act in a reliable or sensible way
Example
The accident was caused by his irresponsibility at work.
その事故は彼の職場での無責任さが原因でした。
C1 adjective /ˌɪlɪˈdʒɪtɪmət/

illegitimate

不正
Meaning
Not authorized by law, rules, or standards; not recognized as valid.
Example
The court ruled the contract to be illegitimate.
裁判所は契約が不正であると判断しました。
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。
C1 noun /ˌɪnækˈtɪvɪti/

inactivity

不活動
Meaning
the state of not being active physically or mentally; lack of action
Example
Prolonged inactivity can negatively affect both physical and mental health.
長期間の不活動は身体的および精神的健康に悪影響を与えます。
C1 adjective /ˈɪndɪɡoʊ bluː/

Indigo-blue

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

indulgent

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

insatiable

満たされない
Meaning
impossible to satisfy; always wanting more
Example
Her insatiable curiosity drove her to read every book in the library.
彼女の満たされない好奇心は、図書館のすべての本を読むように彼女を駆り立てた。
C1 adjective /ɪˈnɒkjuəs/

innocuous

無害な
Meaning
Not harmful or offensive.
Example
His remark was completely innocuous and not meant to offend anyone.
彼の発言は完全に無害で、誰かを傷つける意図はなかった。
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 adjective /ˈɪnərmoʊst/

Innermost

最も深い; 最も個人的な
Meaning
most private and secret; deepest; most personal
Example
She shared her innermost feelings with her closest friend.
彼女は最も深い感情を最も親しい友人と共有しました。
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 noun /ɪˈnɜː.ʃə/

Inertia

慣性; 活動の欠如
Meaning
a tendency to do nothing or remain unchanged; lack of activity or movement
Example
The team's inertia prevented them from adapting to the rapidly changing market conditions.
チームの慣性は、急速に変化する市場の状況に適応するのを妨げました。
C1 verb /ˌɪn.trəˈspekt/

introspect

内省する
Meaning
To examine one's own thoughts, feelings, or mental state.
Example
He often introspects before making important decisions.
彼は重要な決定を下す前にしばしば自己分析をします。
C1 adjective /ˌɪndɪˈvɪzəbl/

indivisible

Meaning
Not able to be divided or separated.
Example
The country's unity was indivisible despite differences.
C1 adjective ˌɪn.tə.dʒen.əˈreɪ.ʃən.əl

intergenerational

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

immortal

不死の
Meaning
living forever; never dying; lasting forever in fame or memory
Example
Legends often describe heroes as immortal beings who never die.
伝説では英雄は不死の存在だとされる。
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 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 ɪnɪɡˈzɔːstɪbəl

inexhaustible

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

inversion

逆転
Meaning
A reversal of the normal order, position, or relationship.
Example
In poetry, inversion is often used to create emphasis.
詩では、逆転は強調を作るためによく使われます。
C1 verb /ˈɪnstɪˌɡeɪt/

instigate

扇動する
Meaning
To bring about or initiate an action, often something negative.
Example
He was accused of instigating the riot.
彼は暴動を扇動したとして告発された。
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 /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 /ɪˈniː.bri.eɪ.tɪd/

inebriated

酔っ払った
Meaning
under the influence of alcohol; drunk
Example
He stumbled into the room completely inebriated.
彼は完全に酔っ払って部屋に入ってきた。
C1 noun /ˈɪntərˌluːd/

interlude

間奏
Meaning
A short period of time that comes between two events; an interval.
Example
There was a brief musical interlude between the two acts of the play.
演劇の二つの幕の間に短い音楽の間奏がありました。
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 noun /ˌɪnkɑːrˈneɪʃən/

incarnation

化身
Meaning
the embodiment of a deity, spirit, or quality in a physical form
Example
The monk was considered the incarnation of compassion.
その僧侶は慈悲の化身と見なされていた。
C1 noun /ˌɪnklɪˈneɪʃən/

inclination

傾向
Meaning
A natural tendency or urge to act or feel in a particular way.
Example
She has an inclination towards helping others.
彼女は他の人を助ける傾向があります。
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 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 adjective ˌɪm.pəˈsɛp.tɪ.bəl

imperceptible

気づかれない
Meaning
So subtle or gradual that it is difficult to notice or perceive
Example
The changes in his behavior were imperceptible at first.
彼の行動の変化は最初は気づかれないものでした。
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 /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。
C1 noun /ˌɪnˈdɪsəplɪn/

indiscipline

規律の欠如
Meaning
lack of discipline or self-control; failure to obey rules or maintain order
Example
Indiscipline among the students disrupted the learning environment.
学生の規律の欠如が学習環境を乱した。
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 noun /ɪmˈpɜːrtɪnəns/

impertinence

無礼
Meaning
lack of respect; rudeness
Example
The teacher was shocked by the student's impertinence.
教師は生徒の無礼さに驚いた。
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 adjective /ɪˈnɔːrdənət/

inordinate

過度の
Meaning
Excessive or unusually large in degree.
Example
She spent an inordinate amount of time on her phone.
彼女は電話に過度の時間を費やしました。
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 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 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 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 noun /ɪnˈtɛstɪn/

intestine

腸
Meaning
The part of the digestive system where food is digested and absorbed, extending from the stomach to the anus.
Example
The doctor explained how nutrients are absorbed in the small intestine.
医者は、小腸で栄養素がどのように吸収されるかを説明しました。
C1 noun /ɪmˌpɜː.sənˈeɪ.ʃən/

impersonation

なりすまし
Meaning
The action of pretending to be another person for the purpose of entertainment or fraud.
Example
Online impersonation is a serious cybercrime.
オンラインでのなりすましは重大なサイバー犯罪です。
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 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 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 /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 adjective /ɪnˈtɒl.ər.ə.bəl/

Intolerable

耐えられない
Meaning
unable to be endured; extremely unpleasant or painful
Example
The noise from the construction site was intolerable.
工事現場の騒音は耐えられないほどひどかった。