inconsistency
All a b c d e f g h i j k l m n o p q r s t u v w x y z
All CEFR A1 A2 B1 B2 C1 C2
Content locale
EN 英語 BN ベンガル語 HI ヒンディー語 ES スペイン語 FR フランス語 DE ドイツ語 RU ロシア語 ZH 中国語 JA 日本語
All Vocabulary Cards All Vocabularies
C1 noun /ˌɪnkənˈsɪstənsi/

inconsistency

不一致
Meaning
The quality of being contradictory, irregular, or not staying the same.
Example
There is an inconsistency between his words and actions.
彼の言葉と行動には不一致があります。
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。
B2 adjective /ɪnˈkluːsɪv/

inclusive

包括的
Meaning
Including all the services, facilities, or items normally expected or required; not excluding any section of society or any party involved.
Example
Inclusive growth benefits all sections of society.
包括的な成長は、社会のすべての層に利益をもたらします。
C2 adjective /ɪmˈplaɪəbl/

impliable

暗示可能な
Meaning
Capable of being implied or suggested.
Example
The meaning of the statement is not directly clear but is impliable from the context.
その声明の意味は直接的には明確ではないが、文脈から推測可能である。
B2 noun /ˈɪmɪɡrənt/

immigrant

移民
Meaning
a person who comes to live permanently in a foreign country
Example
The city has welcomed many new immigrants this year.
今年、市は多くの新しい移民を迎えました。
B2 adjective ˈaɪsəˌleɪtɪd

isolated

孤立した
Meaning
Alone or separated from others; having little or no contact with other people.
Example
Technological advancements often leave people isolated.
技術の進歩はしばしば人々を孤立させる。
C1 noun /ˌɪnkəmˌpætəˈbɪlɪti/

incompatibility

非互換性
Meaning
the state of being unable to exist or work together harmoniously; lack of compatibility
Example
The project failed because of incompatibility between the two software systems.
2つのソフトウェアシステムの非互換性のため、そのプロジェクトは失敗した。
A1 preposition /ɪn ˈfrʌnt əv/

in front of

〜の前に
Meaning
positioned before or ahead of something; facing or located at the forward side of a person or object
Example
She stood in front of the building.
彼女は建物の前に立っていた。
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。
B2 noun /ˌɪnəˈbɪləti/

inability

無能
Meaning
the state of being unable to do something
Example
His inability to make decisions affected his career.
彼の意思決定の無能さは彼のキャリアに影響を与えた。
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 noun /ˌɪnkænˈteɪʃən/

incantation

呪文
Meaning
a series of words used as a magic spell or charm
Example
The wizard chanted an incantation to summon the spirits.
魔法使いは霊を呼び出すために呪文を唱えました。
C1 adjective /ˌɪrɪˈspɛktɪv/

Irrespective

無視して; 問わず
Meaning
without taking something into account; regardless of
Example
All students will be treated equally, irrespective of their background.
すべての学生は、背景に関係なく平等に扱われます。
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 /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。
C2 noun /aɪər/

ire

怒り, 激怒
Meaning
intense anger or rage
Example
The new policy provoked the ire of the employees.
新しい政策は従業員の怒りを引き起こした。
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。
C2 noun /ɪnˈsɪpiəns/

incipience

始まり
Meaning
the beginning or initial stage of something
Example
The project was still in its incipience when funding was approved.
資金提供が承認された時、プロジェクトはまだその始まりの段階にありました。
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 adjective /ˌɪnstɪˈtjuːʃənl/

institutional

制度的
Meaning
Relating to an organization or established practice.
Example
The government made several institutional reforms in education.
政府は教育においていくつかの制度的改革を実施しました。
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。
B2 noun ˈɪndɪkeɪtə

indicator

指標
Meaning
A thing that indicates the state or level of something.
Example
The unemployment rate is a key indicator of economic health.
失業率は経済の健康の重要な指標です。
C1 noun /ɪmˈprɪzənmənt/

imprisonment

投獄
Meaning
the act of putting someone in prison; the state of being confined as punishment
Example
He faced imprisonment for violating the court order.
彼は裁判所の命令に違反して投獄に直面した。
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。
C1 adjective /ˌɪntərˈtwaɪnd/

intertwined

幸福
Meaning
closely connected or twisted together
Example
Their lives became deeply intertwined after the accident.
彼女は賞を受け取ったとき、幸せを隠せませんでした。
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。
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。
C1 verb /ɪmˈplɔːr/

implore

Meaning
To beg someone earnestly or desperately to do something.
Example
She implored him to stay with her.
C2 adjective /ɪnˈsuːpərəbl/

insuperable

克服できない
Meaning
Impossible to overcome or surpass.
Example
The team faced insuperable challenges during the expedition.
チームは遠征中に克服できない課題に直面しました。
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 /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 noun /ɪˌledʒ.əˈbɪl.ə.ti/

Illegibility

読みにくさ
Meaning
the quality of being impossible or difficult to read; unclear writing or print
Example
The doctor's handwriting was famous for its illegibility among the pharmacy staff.
医者の手書きは薬局のスタッフの間でその読みにくさで有名でした。
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。
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 /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 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。
C2 verb /ɪmˈpjuːn/

impugn

Meaning
to dispute the truth, validity, or honesty of a statement or motive
Example
The lawyer tried to impugn the credibility of the witness.
C1 adjective /ɪnˈfriːkwənt/

infrequent

稀な
Meaning
Happening rarely or not often.
Example
He made infrequent visits to his hometown after moving abroad.
彼は海外に移住した後、故郷にあまり頻繁に訪れることはありませんでした。
C1 adjective /ˈɪntrɪkət/

intricate

複雑
Meaning
very detailed, complex, and difficult to understand
Example
The artist created an intricate pattern on the wall.
アーティストは壁に複雑な模様を作り出しました。
C1 noun /ˈɪŋklɪŋ/

inkling

予感
Meaning
A slight idea, hint, or suspicion about something.
Example
She had an inkling that he was planning a surprise.
彼女は彼がサプライズを計画しているという予感を持っていた。
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 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.
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 /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。
B1 noun ˌɪn.stɪˈtjuː.ʃən

institution

機関
Meaning
An organization founded and united for a specific purpose; an established law, practice, or custom.
Example
Institutions play a crucial role in governance.
機関はガバナンスにおいて重要な役割を果たしています。
B1 adjective ˈɪnəveɪtɪv

innovative

革新的な
Meaning
Featuring new methods; advanced and original
Example
Innovative strategies are required to combat pollution.
革新的な戦略が汚染との戦いに必要です。
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。
B2 noun ɪnˈdʒʌstɪs

injustice

不正義
Meaning
Lack of fairness or justice; the practice of being unjust or unfair.
Example
The story portrays the injustices faced by the common people.
物語は一般の人々が直面する不正義を描いています。
C2 noun /ˌɪnkrʌˈsteɪʃən/

incrustation

硬化層
Meaning
a crust or hard coating formed on the surface of something
Example
The old pipes were blocked due to heavy incrustation of minerals.
古いパイプは鉱物の重い硬化層によって詰まっていました。
A2 adverb /ɪˈmiːdiətli/

immediately

直ちに
Meaning
at once; without delay
Example
She responded immediately to the emergency call.
彼女は緊急の電話に直ちに応答した。
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 /aɪˈkɒnəklæst/

iconoclast

偶像破壊者
Meaning
A person who attacks or criticizes cherished beliefs, traditions, or institutions.
Example
He was known as an iconoclast who challenged old traditions.
彼は古い伝統に挑戦した偶像破壊者として知られていました。
C2 adjective /ɪmˈpælpəbəl/

impalpable

触れない
Meaning
unable to be felt by touch; difficult to grasp or understand
Example
There was an impalpable sense of fear in the room.
部屋には触れない恐怖感があった。
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。
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。
C2 noun /ɪnˌtɜːrpəˈleɪʃən/

interpolation

補間
Meaning
The act of inserting something into a text or estimating values within a sequence of data.
Example
The scientist used interpolation to predict the missing data points.
科学者は欠落したデータポイントを予測するために補間を使用しました。
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。
A2 verb /ˌɪntrəˈduːs/

introduce

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

indenture

Meaning
A formal legal agreement, contract, or document, often relating to work or service.
Example
In the 18th century, many workers came under indenture to work overseas.
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 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。
C2 noun /ˌɪntərpəˈzɪʃən/

interposition

介入
Meaning
The act of intervening or coming between two things, often to influence or prevent an outcome.
Example
The manager’s interposition prevented a heated argument from escalating.
マネージャーの介入は、激しい議論がエスカレートするのを防ぎました。
B2 adjective /ɪnˈtækt/

intact

完全
Meaning
Remaining whole, complete, and undamaged.
Example
Despite the storm, the old house remained intact.
嵐にもかかわらず、古い家は完全な状態を保っていました。
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。
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 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 /ɪmˈpɒlɪtnəs/

impoliteness

無礼さ
Meaning
lack of good manners or courtesy; rude behavior
Example
His impoliteness towards the guests shocked everyone.
彼の客に対する無礼さは皆を驚かせた。
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。
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 /ɪnˈsɛp(ə)rəbəl/

inseparable

切り離せない
Meaning
Unable to be separated or always together.
Example
The two friends have been inseparable since childhood.
二人の友達は子供の頃から切り離せないです。
C2 noun /ˌɪnəməˈrɑːtə/

inamorata

Meaning
A woman with whom someone is in love; a female lover.
Example
He wrote a poem dedicated to his inamorata.
C2 adjective /ˈɪnmoʊst/

inmost

最も内面の
Meaning
Situated at the very heart or deepest part; most private or secret.
Example
She revealed her inmost thoughts to her closest friend.
彼女は最も内面的な考えを最も親しい友達に明かした。
B2 noun /ɪnˈvɒlvmənt/

involvement

関与
Meaning
the act of taking part in something
Example
His involvement in the project was crucial.
彼のプロジェクトへの関与は重要だった。
C2 adjective /ɪmˈprɛɡnəbl̩/

impregnable

攻略不可能
Meaning
Unable to be captured, broken into, or defeated.
Example
The fortress was considered impregnable by the enemy.
その要塞は敵によって攻略不可能と見なされていました。
C1 noun /ˌɪntərˈdʒɛkʃən/

interjection

感嘆詞
Meaning
a word or phrase used to express sudden emotion or reaction, often standing alone
Example
Words like 'wow' and 'ouch' are common interjections in English.
'わお'や'痛っ'は英語でよく使われる感嘆詞です。
C2 noun /ɪˈnænɪti/

inanity

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

instant

瞬間
Meaning
A very short period of time; happening immediately.
Example
He replied in an instant without hesitation.
彼は躊躇うことなく瞬時に返答した。
A2 adjective /ˈɪntrəstɪd/

interested

興味がある
Meaning
Showing curiosity or concern about something.
Example
She is very interested in learning new languages.
彼女は新しい言語を学ぶことにとても興味がある。
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 adjective /ˌɪndɪˈvɜːrtɪbəl/

indivertible

Meaning
Not able to be turned aside or diverted.
Example
The judge's indivertible attention was on the case.
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 verb /ɪnˈhɪbɪt/

inhibit

抑制する
Meaning
to prevent or restrain someone or something from acting freely; to hinder
Example
Fear can inhibit personal growth.
恐怖は個人の成長を抑制する可能性があります。
C1 noun /ɪnˈfɜː.mə.ti/

Infirmity

虚弱; 病気; 衰弱
Meaning
physical or mental weakness; a disease or ailment; frailty
Example
Despite his advanced age and various infirmities, he remained mentally sharp and alert.
高齢で多くの病気を抱えていても、彼は精神的に鋭く、警戒心を持ち続けました。
B2 noun /ɪnˈtɜː.prə.tər/

Interpreter

通訳者; 翻訳者;
Meaning
a person who translates orally from one language into another; someone who explains meaning
Example
The international conference hired professional interpreters to translate speeches in real time.
国際会議は、スピーチをリアルタイムで翻訳するためにプロの通訳者を雇いました。
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。
B2 adjective /ˈɪɡ.nər.ənt/

Ignorant

無知
Meaning
lacking knowledge or awareness; uninformed
Example
She was ignorant about the new technology trends.
彼女は新しい技術のトレンドについて無知でした。
B2 adjective /ɪnˈtɒlərənt/

intolerant

不寛容
Meaning
unwilling to accept or respect beliefs or behavior different from one's own
Example
He is intolerant of any opinion that differs from his own.
彼は自分の意見と異なる意見を全く容認しません。
C1 adjective /ɪnˈflæməˌtɔːri/

inflammatory

幸せ
Meaning
causing inflammation in the body; arousing anger, hostility, or strong emotion
Example
His inflammatory speech triggered protests across the city.
彼女は賞を受け取ったとき、幸せそうな表情を隠せなかった。
C1 noun /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 /ɪnˈvɪnsəbl/

invincible

無敵
Meaning
too powerful to be defeated or overcome
Example
The team seemed invincible after winning ten matches in a row.
そのチームは10試合連続で勝利した後、無敵に見えた。
C1 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 /ɪnˈtruː.ʒən/

intrusion

不正侵入
Meaning
Unauthorized entry into a system or place without permission
Example
The company detected an intrusion in its server.
会社はサーバーに侵入を検出しました。
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。
C2 adjective /ɪnˈvaɪələbl/

inviolable

侵害できない
Meaning
never to be broken, dishonored, or violated
Example
Human rights are considered inviolable in modern democracies.
人権は現代の民主主義において侵害できないと見なされています。
B2 adjective /ˈaɪ.dəl/

Idle

怠惰な; 非活動的な; 使われていない
Meaning
lazy; inactive; not working or being used
Example
The factory workers were idle during the strike.
工場の労働者はストライキ中に暇だった。
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。
B2 noun ˌɪn.təˈven.ʃən

intervention

介入
Meaning
The action or process of intervening; involvement in a situation to improve or help it.
Example
The intervention of the UN was crucial in resolving the conflict.
国連の介入は紛争を解決する上で重要だった。
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。
C1 verb /ɪmˈpɛrɪl/

imperil

危険にさらす
Meaning
To put in danger or at risk.
Example
Reckless driving can imperil the lives of others.
無謀な運転は他人の命を危険にさらす可能性があります。
C1 noun /ˌɪn.dɪˈsɪʒ.ən/

Indecision

優柔不断; 決断力の欠如; 迷い
Meaning
the inability to make decisions quickly; uncertainty about what to do
Example
Her indecision about which job offer to accept caused her to miss both opportunities.
どの仕事のオファーを受けるかについての優柔不断さが、両方のチャンスを逃す原因となった。
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。
C2 noun /ɪnˈtɛnʃən/

intension

内的意味
Meaning
The internal content of a concept; the set of attributes implied by a word or phrase.
Example
The intension of the word 'dog' includes being a mammal and domesticated.
'犬'という言葉のインテンションには哺乳類であり、飼いならされたことが含まれます。
B2 adverb /aɪˈrɒnɪkli/

ironically

皮肉にも
Meaning
in a way that is contrary to what is expected or intended
Example
Ironically, the fire station burned down.
皮肉にも、消防署が焼け落ちた。
C1 noun /ɪmˈpɜː.mə.nəns/

impermanence

無常
Meaning
The state or fact of lasting for only a limited period of time.
Example
The philosophy of Buddhism emphasizes the impermanence of life.
仏教の哲学は、人生の無常性を強調します。
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。
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。
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。
C2 adjective /ˈɪnfəntaɪl/

infantile

幼稚な
Meaning
characteristic of an infant; childish
Example
His infantile behavior embarrassed everyone at the meeting.
彼の幼稚な行動は会議でみんなを困らせた。
A2 noun /ˈɪlnəs/

illness

病気
Meaning
A condition of being unwell or suffering from a disease.
Example
She missed school due to a serious illness.
彼女は深刻な病気のため学校を休んだ。
B1 noun ɪnˈven.ʃən

invention

発明
Meaning
The action of inventing something, typically a process or device.
Example
The invention revolutionized communication.
その発明はコミュニケーションを革命的に変えました。
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 /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。
B1 verb /ˈɪndɪkeɪt/

indicate

示す
Meaning
to point out; to show or suggest; to be a sign of
Example
The red light indicates that you should stop.
赤い信号は停止すべきことを示しています。
C2 adjective /ˌɪndɪˈfætɪɡəbl̩/

indefatigable

疲れ知らず
Meaning
persisting tirelessly; incapable of being fatigued
Example
Her indefatigable spirit kept the team motivated during the long project.
彼女の疲れ知らずの精神が、長いプロジェクトを通してチームを励ましました。
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。
C2 adjective /ɪˈræsɪbl/

irascible

怒りっぽい
Meaning
Easily angered; quick-tempered.
Example
His irascible nature often got him into trouble.
彼の怒りっぽい性格はよくトラブルを引き起こしていた。
B2 adjective /aɪˈrɒnɪk/

ironic

皮肉な、風刺的な
Meaning
happening in the opposite way to what is expected, often amusing or sarcastic
Example
It is ironic that the fire station burned down.
消防署が焼けるのは皮肉です。
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。
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。
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。