indulge
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B2 verb /ɪnˈdʌldʒ/

indulge

楽しむ
Meaning
to allow oneself to enjoy something enjoyable, often excessively
Example
He indulged in a piece of chocolate cake after dinner.
彼はディナーの後でチョコレートケーキの一切れを楽しんだ。
B2 noun /ɪnˈdʒɛkʃən/

injection

Meaning
the act of introducing a substance into the body through a needle
Example
The nurse gave me an injection to prevent the infection.
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。
C1 adjective /ˌɪndɪˈfɛnsəbl̩/

indefensible

弁護できない
Meaning
not able to be protected or justified
Example
The minister’s remarks were considered indefensible by the public.
大臣の発言は公衆によって弁護できないとみなされました。
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。
C2 noun /ˈaɪ.ərn.wʊd/

Ironwood

アイアンウッド
Meaning
a hard, dense wood from various trees; also the tree itself that produces small flowers
Example
The ironwood tree blooms with tiny white flowers.
アイアンウッドの木は小さな白い花を咲かせます。
C1 adjective /ɪmˈpɜːrsənl/

impersonal

無個性
Meaning
not influenced by, showing, or involving personal feelings; lacking human warmth or emotion
Example
The letter was written in a very impersonal style.
その手紙は非常に無個性的なスタイルで書かれていました。
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。
C2 noun /ɪnˈtɜːrstɪs/

interstice

隙間
Meaning
a small space that lies between things
Example
Light filtered through the narrow interstices of the wall.
光は壁の狭い隙間を通して漏れた。
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 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。
A2 adjective /ˈɪn.dɔːr/

indoor

屋内の
Meaning
situated, occurring, or used inside a building
Example
Indoor plants can improve air quality at home.
屋内の植物は家の空気の質を改善できます。
C1 noun /ɪnˈdɪf.ər.əns/

Indifference

無関心; 無関心さ; アパシー
Meaning
lack of interest, concern, or sympathy; the state of not caring about something
Example
His indifference to his studies resulted in poor grades throughout the semester.
彼の学業に対する無関心さが、学期中ずっと悪い成績をもたらした。
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。
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.
B2 noun ˌɪmplɪmenˈteɪʃən

implementation

実行
Meaning
The process of putting a decision or plan into effect; execution.
Example
Proper implementation of policies is crucial.
方針の適切な実行は重要です。
C1 verb ɪˈnɔː.ɡjə.reɪ.tɪd

inaugurated

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

imprecise

不正確
Meaning
Not exact or accurate; vague.
Example
His explanation was too imprecise to be helpful.
彼の説明はあまりにも不正確で役に立たなかった。
A1 conjunction /ɪf/

if

もし
Meaning
used to introduce a condition or supposition
Example
If it rains tomorrow, we will stay home.
もし明日雨が降ったら、私たちは家にいます。
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。
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。
B2 verb /ɪnˈsʌlt/

insult

侮辱する
Meaning
to speak or act in a way that hurts someone's feelings or shows disrespect
Example
He felt insulted by her rude comments.
彼は彼女の失礼なコメントで侮辱されたと感じた。
C1 adjective ˌɪn.təˈstel.ər

interstellar

星間の、インターステラ、宇宙の
Meaning
Occurring or situated between stars.
Example
Scientists study interstellar travel possibilities.
科学者たちはインターステラ旅行の可能性を研究しています。
C2 verb /ɪˈmjʊər/

immure

閉じ込める
Meaning
to confine or enclose someone against their will
Example
The prisoner was immured in a dark cell.
囚人は暗い監房に閉じ込められた。
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。
C2 noun /ˌɪnkrɪˈdjuːləti/

incredulity

不信
Meaning
the state of being unwilling or unable to believe something
Example
She looked at him with incredulity after hearing the strange story.
彼女はその奇妙な話を聞いた後、不信のまなざしで彼を見つめた。
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。
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。
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。
B2 noun /ˈɪnˌteɪk/

intake

摂取
Meaning
the process of taking something in, especially food or drink
Example
He monitored his daily intake of calories to maintain a healthy diet.
彼は健康的な食事を維持するために毎日のカロリー摂取量を監視しました。
B2 noun /ˈɪn.vɔɪs/

Invoice

請求書
Meaning
a list of goods sent or services provided, with a statement of the sum due for these
Example
The company sent an invoice for the office supplies delivered last week.
会社は先週配送されたオフィス用品の請求書を送付しました。
C2 adjective /ɪmˈpæsɪbəl/

impassible

無痛性
Meaning
Incapable of suffering or feeling pain (used mainly in theological or philosophical contexts).
Example
Some philosophers argue that God is impassible and cannot experience human emotions.
一部の哲学者は、神は無痛性であり、人間の感情を感じることはできないと主張しています。
A1 adjective /ˈɪntrəstɪŋ/ or /ˈɪntəˌrɛstɪŋ/

interesting

面白い
Meaning
Arousing curiosity or attention; holding one’s interest.
Example
The documentary about space was very interesting.
宇宙についてのドキュメンタリーはとても面白かった。
B2 noun /ˌɪntərˈsɛkʃən/

intersection

交差点
Meaning
a point where two or more things intersect, especially a road or path
Example
The intersection of Main Street and 5th Avenue is always busy.
メインストリートと5番街の交差点はいつも混んでいます。
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 /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。
B1 verb /ɪmˈpɔːrt/

import

輸入する
Meaning
to bring goods or services into a country from abroad; to transfer data
Example
The country imports oil from abroad.
その国は海外から石油を輸入しています。
C2 noun /ˌɪkθiˈɒlədʒɪst/

ichthyologist

魚類学者
Meaning
A scientist who studies fish.
Example
The ichthyologist discovered a new species of fish in the river.
魚類学者は川で新しい魚の種を発見しました。
C1 verb /ɪmˈpɒvərɪʃ/

impoverish

貧困にする
Meaning
To make someone poor or reduce the quality or richness of something.
Example
The long war impoverished the entire nation.
長い戦争が国全体を貧困にした。
C1 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。
B2 adjective /ɪˈmens/

Immense

巨大な; 膨大な; 非常に大きい
Meaning
extremely large or great; huge
Example
The immense mountain range stretched across the horizon.
その巨大な山脈は地平線を越えて広がっていました。
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 verb /ɪˈniː.bri.eɪt/

inebriate

Meaning
to intoxicate; to make someone drunk
Example
The strong wine was enough to inebriate even the most experienced drinker.
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。
B2 noun ɪnˌdʌstrɪəlaɪˈzeɪʃən

industrialization

産業化
Meaning
The development of industries in a country or region on a wide scale.
Example
Industrialization changed the global economy dramatically.
産業化は世界経済を劇的に変えました。
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。
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。
C2 adjective /ɪmˈpræktɪkəbl/

impracticable

実行不可能
Meaning
Not capable of being carried out or put into practice.
Example
The plan seemed impracticable due to limited resources.
資源が限られていたため、計画は実行不可能に見えました。
C2 adjective /ɪˈrædɪkəbəl/

irradicable

根絶不可能な
Meaning
not able to be eradicated; impossible to destroy or remove completely
Example
The love of a mother for her child is irradicable.
母親の子供への愛は根絶不可能です。
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。
C1 adjective /ˌɪnækˈsɛsəbl/

inaccessible

アクセスできない
Meaning
unable to be reached, entered, or understood
Example
The remote village is almost inaccessible during the rainy season.
その遠隔地の村は雨季にはほとんどアクセスできません。
C2 noun /ˌɪnkəˈpæsəti/

incapacity

無能力
Meaning
the lack of ability, power, or fitness to do something
Example
His mental incapacity prevented him from making important decisions.
彼の精神的無能力は、重要な決定を下すのを妨げました。
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 noun /ˌɪnkænˈdɛsəns/

incandescence

白熱光
Meaning
the emission of light from a hot object; brilliance
Example
The incandescence of the candle filled the dark room.
ろうそくの白熱光が暗い部屋を満たしました。
B2 verb /ɪnˈveɪd/

invade

侵入する
Meaning
to enter a place or country forcefully, especially as an enemy
Example
The army invaded the neighboring country.
軍隊は隣国に侵入しました。
C1 noun /ɪnˈsɒm.ni.ə/

Insomnia

不眠症
Meaning
habitual sleeplessness; inability to sleep; the condition of being unable to sleep
Example
Her chronic insomnia made it difficult for her to concentrate during work hours.
彼女の慢性的な不眠症は、仕事中に集中するのを難しくさせた。
B2 adjective /ˌɪnkənˈsɪstənt/

inconsistent

一貫性がない
Meaning
Not staying the same throughout; lacking harmony or regularity.
Example
His answers were inconsistent and confusing.
彼の答えは一貫性がなく、混乱を招いた。
C2 adjective /ɪnˈsɛndiˌɛri/

incendiary

扇動的な / 挑発的な
Meaning
designed to cause fires or stir up conflict
Example
The politician’s incendiary remarks angered the crowd.
政治家の挑発的な発言が群衆を怒らせた。
C1 adjective /ɪnˈsteɪbəl/

instable

不安定な
Meaning
not stable; liable to change, collapse, or fail; lacking firmness or reliability
Example
The instable political situation worried foreign investors.
不安定な政治状況が外国の投資家を心配させた。
B2 adjective /aɪˈdentɪkəl/

Identical

同一の; 全く同じ
Meaning
exactly the same; not different in any way
Example
The twins look completely identical to each other.
双子は完全に同じに見えます。
A2 noun /ˈaɪtəm/

item

アイテム
Meaning
A single thing, object, or unit, often part of a list or collection.
Example
Each item on the list must be checked carefully.
リストの各アイテムは慎重にチェックする必要があります。
C1 adjective /ˌɪnədˈvaɪzəbl/

inadvisable

推奨されない
Meaning
Not recommended; likely to have undesirable consequences.
Example
It is inadvisable to drive in such heavy rain.
このような大雨の中で運転するのは推奨されません。
C2 adjective /ˌɪnæprɪˈhɛnsəbl/

inapprehensible

理解不能
Meaning
not understandable; incomprehensible
Example
The concept was so abstract that it seemed inapprehensible to most students.
その概念は非常に抽象的で、ほとんどの学生には理解できないように思えた。
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。
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。
C2 noun /ˈɪnsələns/

insolence

無礼
Meaning
rude or disrespectful behavior
Example
The teacher was shocked by the student's insolence.
教師は学生の無礼に驚きました。
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。
A2 adverb /ɪnˈdiːd/

indeed

実際に
Meaning
used to emphasize or confirm a statement
Example
It was a long journey indeed.
それは長い旅でした、実際。
C2 adjective /ɪnˈkɒŋɡruənt/

incongruent

不一致な
Meaning
Not in harmony or keeping with the surroundings or other aspects.
Example
His casual outfit looked incongruent at the formal dinner.
彼のカジュアルな服装は正式なディナーで不一致に見えた。
B1 verb /ˌɪntərˈækt/

interact

交流する
Meaning
to communicate or work together with someone or something
Example
Students interact with teachers during class discussions.
学生は授業のディスカッション中に教師と交流します。
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 noun /ɪmˈpjuːnɪti/

impunity

Meaning
freedom from punishment or harmful consequences for an action
Example
The dictator ruled with impunity, ignoring international laws.
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 ˌɪn.tuˈɪʃ.ən

intuition

直感
Meaning
The ability to understand something immediately, without the need for conscious reasoning.
Example
Her intuition told her something was wrong.
彼女の直感は何かが間違っていると言った。
C1 adjective /ɪnˈvɛntɪv/

inventive

創造的
Meaning
Having the ability to create or design new things or to think originally.
Example
The inventor was known for his inventive solutions to everyday problems.
発明家は日常の問題に対する創造的な解決策で知られていた。
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 /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。
C1 adjective /ɪnˈstɪŋk.tɪv/

instinctive

本能的, 自然な, 自動的
Meaning
Based on instinct; done without conscious thought; natural and automatic.
Example
His instinctive reaction saved his life.
彼の本能的な反応は彼の命を救った。
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 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。
A2 noun /ˈɪn.sekt/

Insect

昆虫
Meaning
a small invertebrate animal with six legs and usually one or two pairs of wings
Example
The butterfly is a beautiful insect that flies from flower to flower.
蝶は花から花へと飛ぶ美しい昆虫です。
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 /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。
C2 adjective /ˈɪkθiɪk/

ichthyic

魚のような
Meaning
Relating to or resembling fish.
Example
The artist's painting had an ichthyic quality.
アーティストの絵には魚のような特徴がありました。
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。
B2 noun /ˌaɪ.səˈleɪ.ʃən/

Isolation

隔離
Meaning
the process or fact of isolating or being isolated; separation from other people or things
Example
The patient was kept in isolation to prevent the spread of the infectious disease.
患者は感染症の拡大を防ぐために隔離されました。
C1 adjective /ɪnˈɔːdəbl/

inaudible

聞こえない
Meaning
Unable to be heard.
Example
Her voice was almost inaudible over the noise.
その音の中で彼女の声はほとんど聞こえなかった。
B2 adjective /ɪˈmædʒɪnəbl/

imaginable

想像できる
Meaning
Capable of being imagined or conceived.
Example
They offered every imaginable type of food at the festival.
彼らはフェスティバルであらゆる想像できるタイプの食べ物を提供しました。
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。
B2 adjective /ɪnˈdɪf.ər.ənt/

indifferent

無関心
Meaning
having no particular interest or concern; not caring one way or another
Example
She was indifferent to the outcome of the match.
彼女は試合の結果に無関心だった。
B2 verb /ɪtʃ/

itch

かゆみ
Meaning
to feel an urge to scratch; to have a restless desire
Example
My skin itches from the mosquito bites.
蚊に刺されて肌がかゆいです。
C2 noun /ˌɪnvəˈluːʃən/

involution

インヴォリューション
Meaning
a complicated or intricate form or state; in biology, the shrinking of an organ after its function has finished
Example
The story was full of involution, making it hard to follow.
その話はインヴォリューションで満ちており、追うのが難しかった。
B1 adjective /ɪmˈpeɪʃənt/

impatient

イライラ
Meaning
Not able to wait calmly; restless and eager for something to happen.
Example
She grew impatient while waiting in the long queue.
彼女は長い列で待っている間にイライラしてきた。
B2 noun, verb /ˌɪnkənˈviːniəns/

inconvenience

不便
Meaning
trouble or difficulty caused to someone; to cause trouble or difficulty to someone
Example
We apologize for any inconvenience caused by the delay.
遅延によって生じた不便についてお詫びします。
C2 verb /ɪmˈpeɪl/

impale

突き刺す
Meaning
to pierce or fix something with a sharp object
Example
The knight was impaled by the enemy’s spear.
騎士は敵の槍で突き刺さった。
C1 adjective /ˌɪnsɪˈdɛntəl/

incidental

付随的
Meaning
happening as a minor part or in connection with something else
Example
Incidental expenses like snacks and tips were included in the bill.
スナックやチップのような付随的な費用は請求書に含まれていました。
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。
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 adjective /ɪmˈplækəbl/

implacable

容赦しない
Meaning
unable to be appeased, calmed, or pacified
Example
The soldiers faced an implacable enemy who refused to surrender.
兵士たちは降伏を拒否した容赦しない敵に直面した。
B2 adjective /ˈɪnˌsaɪtfəl/

insightful

洞察力のある
Meaning
Showing deep understanding or perceptiveness.
Example
The professor gave an insightful lecture on global economics.
教授はグローバル経済に関する洞察力のある講義を行いました。
B2 noun /ɪnˈfɪnɪti/

infinity

無限
Meaning
A concept describing something without any limit or end.
Example
The universe seems to stretch into infinity.
宇宙は無限に広がっているように見える。
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 adjective /ɪnˈveə.ri.ə.bəl/

Invariable

不変の; 一定の; 常に同じ
Meaning
never changing; constant; always the same
Example
His invariable routine includes morning exercise and coffee.
彼の不変のルーチンには、朝の運動とコーヒーが含まれています。
C2 adjective /ɪnˈdʒɛnjuəs/

ingenuous

無邪気
Meaning
Innocent, naive, and unsuspecting; showing childlike simplicity and sincerity.
Example
Her ingenuous smile revealed her genuine kindness.
彼女の無邪気な笑顔は彼女の本当の優しさを明らかにしました。
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。
C2 adjective /ɪnˈɛk.wɪ.tə.bəl/

inequitable

不公平な
Meaning
Not fair or just; lacking in fairness or equality.
Example
The distribution of resources was inequitable among the workers.
リソースの分配は労働者の間で不平等でした。
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。
B2 verb /ɪnˈspekt/

inspect

検査する
Meaning
to examine something carefully to check for problems or faults
Example
The engineer will inspect the building for structural damage.
エンジニアは建物の構造的な損傷を検査します。
C2 adjective /ˌɪrɪˈmiːdiəbl̩/

irremediable

修復不可能
Meaning
Impossible to cure, repair, or remedy.
Example
The damage to the ancient manuscript was irremediable.
古代の写本への損傷は修復不可能でした。
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 verb /ɪnˈtɪmɪdeɪt/

intimidate

Meaning
To frighten or overawe someone, especially to make them do what one wants.
Example
The bully tried to intimidate the smaller kids.
B2 adjective /ɪmˈprɒp.ər/

Improper

不適切な; 不正確な; 不適当な
Meaning
inappropriate; incorrect; not suitable
Example
It would be improper to discuss personal matters in a business meeting.
ビジネス会議で個人的な事柄を議論するのは不適切です。
B2 noun /ˌɪmɪˈɡreɪʃən/

immigration

移民
Meaning
the action of coming to live permanently in a foreign country
Example
Immigration policies vary from country to country.
移民政策は国によって異なります。
C2 noun /ɪmˈpjuːɪsəns/

impuissance

無力, 無能
Meaning
inability to take effective action; helplessness
Example
The government’s impuissance in the face of crisis frustrated the people.
危機の前で政府の無力さが人々を失望させた。
B1 adjective /ɪmˈpres.ɪv/

Impressive

印象的な
Meaning
striking; remarkable; having the ability to impress
Example
Her impressive performance earned her a standing ovation.
彼女の印象的な演技はスタンディングオベーションを受けた。
C2 adjective /ɪnˈtræn.sɪ.dʒənt/

intransigent

頑固な, 譲らない, 固執した
Meaning
Unwilling or refusing to change one's views or to agree about something.
Example
His intransigent stance delayed the agreement.
彼の頑固な態度が合意を遅らせました。
C1 noun ɪnˈdʌldʒəns

indulgence

嗜好
Meaning
The practice of allowing oneself to enjoy the pleasure of something.
Example
His indulgence in junk food affected his health.
彼のジャンクフードへの過度の嗜好は健康を害した。
A1 noun /ˈaɪs kriːm/

Ice-cream

アイスクリーム
Meaning
a frozen sweet dessert made from dairy products, usually served cold
Example
Children love to eat ice-cream on hot summer days.
子供たちは暑い夏の日にアイスクリームを食べるのが好きです。
B2 noun /ˈɪntərvəl/

interval

インターバル
Meaning
a period of time between two events or points; a pause or break in activity
Example
There was a short interval between the two performances.
二つの公演の間には短いインターバルがありました。
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。
B2 adjective /ˈɪnfɪnɪt/

infinite

無限
Meaning
limitless or endless in space, extent, or number
Example
The universe is often described as infinite.
宇宙はしばしば無限だと説明されます。