inexpressible
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C2 adjective /ˌɪnɪkˈsprɛsəbl/

inexpressible

言葉では表現できない
Meaning
Too strong or extreme to be expressed in words.
Example
She felt inexpressible joy at the news of her success.
彼女は成功の知らせを聞いて言葉では表現できない喜びを感じた。
B2 adjective /ˈɪmɪnənt/

imminent

差し迫った
Meaning
About to happen; likely to occur very soon.
Example
Dark clouds signaled that a storm was imminent.
暗い雲は嵐が迫っていることを示していた。
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。
C2 noun /ˌɪnvəˈkeɪʃən/

invocation

祈願
Meaning
the act of calling upon a higher power for help, blessing, or inspiration
Example
The ceremony began with an invocation to the gods.
儀式は神々への祈願から始まりました。
C2 verb /ˌɪmpɔːrˈtuːnd/

importuned

しつこく頼む
Meaning
asked someone persistently and pressingly for something
Example
She importuned her boss for a raise until he finally gave in.
彼女は昇給を求めて上司にしつこく頼んだ、彼がとうとう折れたまで。
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。
B2 adjective /ɪnˈsɛnsətɪv/

insensitive

無神経な
Meaning
Showing or feeling no concern for others' feelings.
Example
His insensitive comment hurt her deeply.
彼の無神経なコメントは彼女を深く傷つけました。
C1 noun /ɪˌluːmɪˈneɪʃən/

illumination

Meaning
the act of lighting something or making something clear
Example
The street was filled with bright illumination from the lamps.
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。
C1 adjective /ɪnˈfæləbl̩/

infallible

間違いない
Meaning
incapable of making mistakes or being wrong
Example
Her judgment seemed infallible in matters of finance.
彼女の判断は財務問題において間違いないように見えた。
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 /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 /ɪnˈkrɛdjələs/

incredulous

Meaning
unwilling or unable to believe something
Example
He gave her an incredulous look when she claimed she could fly.
C1 adjective ˌɪn.təˈdɪs.ɪ.plɪ.nər.i

interdisciplinary

学際的
Meaning
Relating to more than one branch of knowledge.
Example
The interdisciplinary approach in education enhances problem-solving skills.
教育における学際的アプローチは、問題解決スキルを向上させる。
B2 verb /ɪˈnɪʃieɪt/

initiate

開始する
Meaning
to begin or start; to introduce someone to a new activity
Example
The company will initiate a new training program.
会社は新しい研修プログラムを開始します。
C2 noun /ˈaɪsinəs/

iciness

冷たさ
Meaning
The state of being cold in manner or temperature.
Example
There was a distinct iciness in his voice.
彼の声には明確な冷たさがあった。
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。
B2 adjective /ɪmˈpɜːrfɪkt/

imperfect

不完全
Meaning
Not perfect; having faults or flaws.
Example
The painting was beautiful despite being imperfect.
その絵は美しかったが、完璧ではなかった。
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 /ɪmˈpɛtʃ.u.əs/

impetuous

衝動的な
Meaning
Acting or done quickly and without thought or care; impulsive.
Example
His impetuous decision led to unexpected consequences.
彼の衝動的な決断は予想外の結果を招いた。
C1 noun /ɪmˌpɒsəˈbɪlɪti/

impossibility

不可能性
Meaning
the state or fact of being impossible; something that cannot be done or achieved
Example
Finishing the project in one day was an impossibility.
一日でそのプロジェクトを終えるのは不可能だった。
B2 verb /ˈɪl.ə.streɪt/

illustrate

説明する
Meaning
to explain or make something clear by using examples, pictures, or comparisons
Example
The teacher used diagrams to illustrate the concept.
先生はその概念を説明するために図を使いました。
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。
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。
B2 verb /ˈɪmɪteɪt/

imitate

真似る
Meaning
to copy the behavior or manner of someone or something
Example
Children often imitate their parents' behavior.
子供たちはしばしば親の行動を真似します。
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。
C1 adjective ɪnˈdel.ə.bəl

indelible

消えない
Meaning
Making marks that cannot be removed; impossible to forget or remove.
Example
Her speech left an indelible mark on the audience.
彼女のスピーチは聴衆に消えない印象を残しました。
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。
C2 verb /ˈɪməleɪt/

immolate

犠牲にする/焼死させる
Meaning
To kill or sacrifice, especially by burning.
Example
The protesters threatened to immolate themselves in front of the building.
抗議者たちは建物の前で自ら火にくべると脅した。
C1 adjective /ɪmˈpæsɪv/

impassive

無表情
Meaning
Not showing or feeling emotion; expressionless.
Example
Despite the shocking news, she remained impassive.
衝撃的なニュースにもかかわらず、彼女は無表情のままでした。
C1 adjective /ɪˈlɪsɪt/

illicit

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

inject

注射する
Meaning
To introduce a substance, especially a drug, into the body using a needle.
Example
The nurse will inject the vaccine into the patient's arm.
看護師は患者の腕にワクチンを注射します。
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。
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。
B2 noun /ˌɪnsɪˈkjʊərɪti/

insecurity

不安感
Meaning
lack of confidence or assurance; a state of uncertainty or vulnerability
Example
Her insecurity made her doubt her abilities despite her experience.
彼女の不安感は彼女に自分の能力を疑わせた。
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 ˌɪnfɛsˈteɪʃən

infestation

侵入, 異常に大量の昆虫や動物がある場所に存在すること
Meaning
The presence of an unusually large number of insects or animals in a place, causing damage or disease.
Example
The infestation of ants in the kitchen led to immediate pest control measures.
キッチンにおけるアリの侵入は、即座に害虫駆除対策を講じる結果となった。
C2 adjective /ˌɪnkəˈməʊdiəs/

incommodious

不快な
Meaning
Uncomfortably small, cramped, or inconvenient.
Example
We had to stay in an incommodious room during the trip.
旅行中に不快な部屋に泊まらなければなりませんでした。
B2 noun ˈɪn.frəˌstrʌk.tʃər

infrastructure

インフラストラクチャー
Meaning
The basic physical and organizational structures and facilities needed for the operation of a society or enterprise.
Example
Digital infrastructure is vital for future advancements.
デジタルインフラストラクチャーは将来の進歩にとって不可欠です。
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 /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 adjective ɪnˈkʌm.bənt

incumbent

義務的な
Meaning
necessary for (someone) as a duty or responsibility.
Example
It is incumbent upon all citizens to obey the law.
すべての市民が法律を守るのは義務である。
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。
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 verb /ɪnˈsaɪt/

incite

扇動する
Meaning
to provoke; to stir up
Example
His speech incited the crowd to violence.
彼のスピーチは群衆を暴力に駆り立てた。
C1 adjective /ˈaɪərnˌklæd/

ironclad

鉄壁の
Meaning
impossible to change, break, or dispute; very strong and firm
Example
The company had an ironclad contract with its suppliers.
その会社はサプライヤーと鉄壁の契約を結んでいた。
C1 adjective /ɪnˈtɛlɪdʒəbl/

intelligible

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

isthmus

地峡
Meaning
A narrow strip of land connecting two larger land areas, often with water on either side.
Example
The Panama Canal cuts through the Isthmus of Panama.
パナマ運河はパナマの地峡を通ります。
A2 noun /ˈɪʃ.uːz/

issues

問題
Meaning
Important topics or problems for debate or discussion.
Example
Health issues from pollution are increasing.
汚染による健康問題が増加しています。
C2 noun /ɪˈluːmɪnənt/

illuminant

光源
Meaning
A substance or device that produces light.
Example
The lamp acted as an illuminant in the dark cave.
ランプは暗い洞窟で光源として機能しました。
C1 adjective /ɪˈneɪn/

inane

無意味な, 馬鹿な
Meaning
lacking sense, meaning, or significance; silly or pointless
Example
The movie was criticized for its inane dialogue.
その映画は無意味なセリフで批判された。
B2 noun /ɪnˈdʌstriəl ˌrɛvəˈluːʃən/

Industrial Revolution

産業革命
Meaning
The rapid development of industry that occurred in Britain in the late 18th and 19th centuries, brought about by the introduction of machinery and characterized by the use of steam power and the growth of factories.
Example
The Industrial Revolution marked a shift in production processes.
産業革命は生産プロセスにおける変化を示しました。
B2 noun /ɪnˈhæbɪtənt/

inhabitant

住民
Meaning
a person or animal that lives in a particular place
Example
The inhabitants of the village rely on farming for their livelihood.
村の住民は生活のために農業に頼っています。
C1 verb /ɪmˈpɛl/

impel

Meaning
to drive, force, or urge someone to do something
Example
Her curiosity impelled her to open the mysterious box.
B2 adjective /ˌɪnkəmˈpliːt/

incomplete

不完全
Meaning
Not finished, lacking some parts or not whole.
Example
Her report was incomplete and needed further details.
彼女の報告は不完全で、詳細が必要でした。
C1 noun /ˌɪnkəmˈpliːtnəs/

incompleteness

不完全さ
Meaning
the state of not being complete or whole; lack of necessary parts or fullness
Example
The incompleteness of the report caused delays in the project.
レポートの不完全さがプロジェクトの遅れを引き起こした。
C1 noun /ɪmˈpjʊərəti/

impurity

不純物
Meaning
the state of being unclean or contaminated; a substance that makes something impure
Example
The scientist removed every impurity from the water sample.
科学者は水のサンプルからすべての不純物を取り除いた。
C2 adjective /ˌɪrɪˈdjuːsəbl/

irreducible

不可約
Meaning
impossible to reduce or simplify further
Example
The fraction 3/7 is irreducible.
分数 3/7 は不可約です。
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。
A2 verb /ɪnˈkri:s/

increase

増加
Meaning
to become or make something larger in amount, number, or degree
Example
The company plans to increase its production this year.
その会社は今年、生産を増加させる予定です。
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 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 /ˌɪndɪˈstɪŋkt/

indistinct

不明瞭な
Meaning
Not clear or sharply defined; vague or blurred.
Example
The sound of voices was indistinct in the distance.
遠くからの声は不明瞭でした。
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 noun /ˈɪndɪkənt/

indicant

指標
Meaning
Something that indicates or points to a fact or condition.
Example
High fever is often an indicant of infection.
高熱はしばしば感染の指標となります。
C1 adjective /ˈɪnfəməs/

infamous

悪名高い
Meaning
well known for some bad quality or deed
Example
The dictator was infamous for his cruelty.
その独裁者はその残虐さで悪名高かった。
C1 noun /ɪnˈækjʊrəsi/

inaccuracy

不正確さ
Meaning
lack of accuracy or precision; an incorrect or wrong detail
Example
The report contained several factual inaccuracies.
その報告書にはいくつかの不正確さがあった。
C1 adjective, noun /ˈɪnvəlɪd/ (adjective), /ɪnˈvælɪd/ (noun)

invalid

無効
Meaning
Not valid; having no force or effect. Also refers to a person too weak or ill to care for themselves.
Example
The court declared the contract invalid.
裁判所は契約を無効と宣言した。
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。
C1 noun /ˈɪd.i.əm/

idiom

イディオム
Meaning
A group of words whose meaning is different from the meanings of the individual words.
Example
The idiom 'break the ice' means to start a conversation in a friendly way.
イディオム '氷を破る' は、友好的な方法で会話を始めることを意味します。
B2 noun /ˈɪm.pʌls/

Impulse

衝動; 突然の欲求
Meaning
a sudden strong and unreflective urge or desire to act; a driving force or motivation
Example
She bought the expensive dress on impulse and later regretted the purchase.
彼女は衝動で高価なドレスを買い、後でその購入を後悔しました。
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。
A2 noun, verb /ˈɪʃuː/

issue

問題, 発行, 配布
Meaning
A problem, topic, or the act of supplying or distributing something.
Example
The magazine will issue a new edition next week.
雑誌は来週新しい版を発行します。
B1 adjective /ɪˈnɪʃəl/

initial

初期の
Meaning
Existing or occurring at the beginning.
Example
Her initial reaction was one of surprise.
彼女の初期の反応は驚きだった。
C1 adjective /ɪmˈpɛndɪŋ/

impending

差し迫った
Meaning
about to happen soon, usually something unpleasant or threatening
Example
The villagers were worried about the impending flood.
村人たちは差し迫った洪水を心配していた。
C2 noun /ɪˈmɒdəsti/

immodesty

不謹慎
Meaning
lack of modesty or decency; behavior or attitude that is overly bold or improper
Example
The article was criticized for its tone of immodesty.
その記事は不謹慎な語調で批判された。
C1 verb ɪˈnɪʃɪeɪtɪd

initiated

開始された
Meaning
Caused a process or action to begin; started something.
Example
The project was initiated to enhance marine biodiversity.
プロジェクトは海洋生物多様性を向上させるために開始されました。
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 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 adjective /ɪˈrɛləvənt/

Irrelevant

無関係な
Meaning
not connected with or relevant to something; having no bearing on the matter
Example
Your past mistakes are irrelevant to this discussion.
あなたの過去の過ちはこの議論には無関係です。
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。
A1 preposition /ˈɪntuː/

into

中へ
Meaning
expressing movement or direction to the inside of something
Example
She walked into the room quietly.
彼女は静かに部屋に入った。
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 /ˌɪrɪˈprəʊtʃəbl̩/

irreproachable

非の打ち所がない
Meaning
Beyond criticism; faultless.
Example
The judge was known for his irreproachable integrity.
その裁判官は非の打ち所がない誠実さで知られていた。
C2 adjective /ɪmˈpɛn.ɪ.tənt/

impenitent

後悔しない
Meaning
Not feeling regret or shame about one's actions.
Example
The criminal remained impenitent after the trial.
犯人は裁判後も後悔しないままでした。
C1 adjective ˌɪn.trəˈspek.tɪv

introspective

内省的
Meaning
Characterized by or given to introspection; examining one's own thoughts and feelings.
Example
Writers tend to be highly introspective individuals.
作家はしばしば非常に内省的な人々である。
C1 adjective ˌɪn.krəˈmen.təl

incremental

増分的
Meaning
Relating to or denoting an increase or addition, especially one of a series on a fixed scale; proceeding in small stages.
Example
Incremental changes ensure sustainability.
増分的な変化は持続可能性を確保します。
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。
B2 adjective /ɪˈmjuːn/

immune

免疫の
Meaning
protected from disease or from the effects of something
Example
Children who are vaccinated are immune to many diseases.
予防接種を受けた子供たちは多くの病気に免疫があります。
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。
C1 adverb ɪnˈtrɪn.zɪ.kli

intrinsically

本質的に
Meaning
In a way that is naturally or inherently part of something's essential nature.
Example
Some people are intrinsically motivated to learn.
いくつかの人々は本質的に学ぶことに動機づけられている。
C1 noun /ˌɪməˈtjʊərəti/

immaturity

未熟さ
Meaning
the state of not being fully developed emotionally, mentally, or physically; lack of maturity
Example
His immaturity made it difficult for him to handle responsibility.
彼の未熟さは責任を果たすことを難しくした。
C2 adjective /ˌɪnfəˈlɪsɪtəs/

infelicitous

不適切な
Meaning
not suitable or well chosen; awkward or unfortunate
Example
His infelicitous remark ruined the atmosphere of the meeting.
彼の不適切な発言は会議の雰囲気を台無しにしました。
B2 adjective /ɪsˈlɑːmɪk/

islamic

イスラームの
Meaning
relating to Islam, its followers, or its teachings
Example
The city has many Islamic cultural centers.
その都市には多くのイスラーム文化センターがあります。
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 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。
B2 verb /ˈɪntɪɡreɪt/

integrate

統合する
Meaning
To combine or bring together into a unified whole.
Example
The new system integrates data from multiple sources.
新しいシステムは複数のソースからデータを統合します。
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。
C1 adjective /ɪˈnuːmərəbəl/

Innumerable

無数; 数えきれない; 無限
Meaning
too many to be counted; countless; infinite in number
Example
There are innumerable stars in the night sky that we cannot see with our naked eyes.
夜空には数えきれない星があり、私たちは裸眼では見ることができません。
C1 noun /ɪˈrɛlɪvənsi/

irrelevancy

無関係性
Meaning
the state of being unrelated or unimportant to the matter at hand
Example
The judge dismissed the argument because of its irrelevancy to the case.
裁判官はその主張が事件と無関係であるとして退けた。
A1 pronoun /ɪt/

it

それ
Meaning
used to refer to a thing, animal, or idea previously mentioned or easily identified
Example
It is raining outside.
外では雨が降っています。
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。
C1 adjective /ɪˈnɜːrt/

inert

不活性
Meaning
lacking the ability or strength to move or act; chemically inactive
Example
The patient remained inert on the bed.
患者はベッドで動かずにじっとしていました。
C2 adjective /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。
B2 verb /ˈɪr.ɪ.teɪt/

irritate

イライラさせる
Meaning
To make someone annoyed or angry; to cause discomfort or inflammation.
Example
Rubbing your eyes can irritate them.
目をこすると、それが刺激になることがあります。
B2 noun /ɪnˈtɒlərəns/

intolerance

不寛容
Meaning
unwillingness to accept or endure beliefs, behaviors, or conditions different from one's own
Example
The leader was criticized for his intolerance toward other religions.
リーダーは他の宗教に対する不寛容さで批判されました。
C2 noun /ɪmˈpɒs.tʃər/

Imposture

偽装; 詐欺; 虚偽
Meaning
the practice of deceiving others by pretending to be someone else; fraudulent deception
Example
The elaborate imposture lasted for months before investigators uncovered the truth.
その精巧な詐欺は数ヶ月続き、調査員が真実を明らかにするまで続いた。
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。
B2 adjective, noun /ɪzˈreɪli/

israeli

イスラエルの
Meaning
relating to Israel or its people; a person from Israel
Example
She works for an Israeli company.
彼女はイスラエルの会社で働いています。
B1 adverb /ɪnˈkrɛdɪbli/

incredibly

信じられないほど
Meaning
to a great degree; extremely or unbelievably
Example
The view from the top of the mountain was incredibly beautiful.
山頂からの景色は信じられないほど美しかった。
C1 adjective /ˌaɪ.di.əˈlɒdʒ.ɪ.kəl/

ideological

イデオロギー的
Meaning
Relating to or based on a system of ideas or beliefs.
Example
The two parties are divided by deep ideological differences.
二つの党は深いイデオロギー的な違いによって分裂している。
B2 noun /ɪnˌtɜːrprəˈteɪʃən/

interpretation

解釈
Meaning
the action of explaining the meaning of something
Example
The teacher gave her own interpretation of the poem.
教師は詩の自分の解釈を示しました。
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 /ɪnˈkɑːdʒɪtənt/

incogitant

無思慮な
Meaning
Lacking thought; inconsiderate or thoughtless.
Example
It was incogitant of him to make such a rude comment.
彼がそんな失礼なコメントをするのは無思慮なことでした。
A2 adjective ˌɪn.təˈnæʃ.ən.əl

international

国際的な
Meaning
Existing, occurring, or carried on between two or more nations and their citizens.
Example
International standards improve competitiveness.
国際基準は競争力を高めます。
C1 adjective /ˌɪndɪˈstrʌktəbl/

indestructible

壊れない
Meaning
Impossible to destroy or break.
Example
The superhero's shield was said to be indestructible.
スーパーヒーローの盾は壊れないと言われていました。
C2 adjective /ˌɪmpɪˈkjuːniəs/

impecunious

貧乏
Meaning
Having little or no money; poor.
Example
He grew up in an impecunious family.
彼は貧乏な家族で育ちました。
C1 adjective /ˌɪntərˈtʃeɪndʒəbl/

interchangeable

交換可能な
Meaning
able to be exchanged with each other without difference or loss of function
Example
These machine parts are interchangeable, so they can be replaced easily.
これらの機械部品は交換可能なため、簡単に交換できます。
B1 noun aɪˈdɛntɪti

identity

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