inadvertence
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C2 noun /ˌɪnədˈvɜːrtəns/

inadvertence

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

isothermal

等温
Meaning
Having or maintaining equal or constant temperature.
Example
The experiment was conducted under isothermal conditions.
実験は等温条件で行われました。
A1 noun /aɪˈdiː.ə/

Idea

アイデア; 概念; 提案
Meaning
a thought or suggestion as to a possible course of action; a concept or mental impression
Example
She had a brilliant idea for solving the company's efficiency problem.
彼女は会社の効率問題を解決するための素晴らしいアイデアを持っていました。
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 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。
C1 verb /ɪnˈsɪnjueɪt/

insinuate

Meaning
To suggest or hint something indirectly and often unpleasantly.
Example
He insinuated that she had lied about her qualifications.
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 adverb /ˌɪn.ədˈvɜːr.tənt.li/

Inadvertently

うっかり; ついうっかり; 誤って
Meaning
without being aware of what you are doing; unintentionally; by mistake
Example
She inadvertently deleted the important file while cleaning her computer.
彼女はコンピュータを掃除しているとき、重要なファイルをうっかり削除してしまった。
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。
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 /ˌɪntərˈrɛɡnəm/

interregnum

政権空白期
Meaning
A period between rulers or governments when normal leadership is suspended.
Example
The country faced instability during the interregnum after the king’s death.
国王の死後、国は政権空白期に不安定さに直面した。
C2 noun /ˈɪrɪɡənt/

irrigant

灌漑液
Meaning
A liquid used for irrigation, especially in medical or agricultural contexts.
Example
The doctor used a sterile irrigant during the procedure.
医師は手術中に無菌の灌漑液を使用しました。
C2 adjective /ɪnˈklɛmɛnt/

inclement

悪天候
Meaning
unpleasantly cold, wet, or stormy (usually weather)
Example
The match was canceled due to inclement weather.
試合は悪天候のためキャンセルされました。
C2 noun /ɪnˈsaɪzər/

incisor

切歯
Meaning
a narrow-edged tooth at the front of the mouth, adapted for cutting
Example
The dentist noted that his upper left incisor was chipped.
歯科医は彼の上の左側の切歯が欠けていることに気づきました。
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。
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。
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。
B1 adjective ˌɪn.dɪˈpen.dənt

independent

独立
Meaning
Not depending on another for livelihood or subsistence; free from outside control; not subject to another's authority.
Example
An independent institution ensures transparency in governance.
独立した機関は、ガバナンスの透明性を保証します。
C2 noun /ˌɪmprəˈsɑːrioʊ/

impresario

プロデューサー
Meaning
A person who organizes or finances concerts, plays, or operas.
Example
The impresario arranged a series of concerts for the rising star.
インプレサリオは、急成長するスターのためにコンサートのシリーズを手配しました。
C2 verb /ˌɪmpɔːrˈtuːn/

importune

しつこく頼む
Meaning
To ask someone persistently or pressingly for something
Example
The child importuned his mother for a new toy.
その子供は新しいおもちゃを欲しがって母親にしつこく頼んだ。
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。
B1 noun /ɪnˌvɛs.tɪˈɡeɪ.ʃən/

investigation

調査
Meaning
the process of inquiring into or examining something carefully to find the truth
Example
The investigation revealed new evidence about the fraud.
調査は詐欺に関する新しい証拠を明らかにしました。
C1 noun ˌɪrɪˈvɜːrsəbl ˈdæmɪdʒ

irreversible damage

取り返しのつかない損害
Meaning
Harm or injury that cannot be undone or repaired.
Example
Climate change causes irreversible damage to ecosystems.
気候変動は生態系に取り返しのつかない損害を与えます。
B1 noun ɪmˈpruːv.mənts

improvements

改善
Meaning
The action of making or becoming better; an instance of something becoming or being made better.
Example
Continuous improvements increase productivity.
継続的な改善は生産性を高めます。
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。
C1 adjective /ɪˈmeʒərəbəl/

Immeasurable

計り知れない
Meaning
too large or extensive to measure; boundless
Example
The immeasurable love of a mother knows no bounds.
母の計り知れない愛には限界がない。
C2 adjective ˌɪn.ɪ.fɪˈkeɪ.ʃəs

inefficacious

効果がない
Meaning
Not producing any or the desired effect; ineffective.
Example
The treatment was inefficacious in curing the disease.
その治療法は病気の治癒に効果がありませんでした。
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。
B2 adjective ˈɪn.tɪ.ɡrəl

integral

不可欠
Meaning
Necessary to make a complete whole; essential or fundamental.
Example
Exercise is an integral part of a healthy lifestyle.
運動は健康的なライフスタイルの不可欠な部分です。
B1 verb ɪnˈkriːsɪŋ

increasing

増加
Meaning
Becoming or making greater in size, amount, intensity, or degree; growing.
Example
Increasing awareness about education is necessary.
教育に対する認識を高めることが必要です。
B1 noun /ˌɪntərˈækʃən/

interaction

相互作用
Meaning
The process of people or things acting upon or influencing each other.
Example
The teacher encouraged more interaction between students.
教師は生徒間のさらなるインタラクションを促進しました。
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。
B2 adjective /ɪmˈplɪsɪt/

implicit

暗黙の
Meaning
Suggested or understood without being directly stated.
Example
Her trust in him was implicit.
彼女の彼に対する信頼は暗黙のものでした。
C2 noun /ˈɪnroʊd/

inroad

進展
Meaning
An advance or significant progress, often at the expense of something else.
Example
The company made significant inroads into the mobile market.
その会社はモバイル市場で重要な進展を遂げました。
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。
C2 noun /aɪˈdɒlətri/

idolatry

偶像崇拝
Meaning
The worship of idols or extreme admiration for someone or something.
Example
The priest condemned the idolatry practiced in the village.
司祭は村で行われている偶像崇拝を非難した。
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。
C2 conjunction /ˌɪnəzˈmʌtʃ æz/

inasmuch-as

なぜなら
Meaning
Because; since.
Example
He cannot attend, inasmuch as he is unwell.
彼は出席できません、なぜなら彼は病気だからです。
B2 verb /ɪnˈheɪl/

inhale

吸う
Meaning
to breathe in; to draw air into the lungs
Example
Take a deep breath and inhale slowly.
深く息を吸い、ゆっくり吸い込みます。
C2 noun /ˌɪn.təˈvɛn.ʃə.nɪ.zəm/

interventionism

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

insouciant

無頓着
Meaning
Showing a casual lack of concern; carefree.
Example
He gave an insouciant shrug and walked away.
彼は無頓着に肩をすくめて、歩き去った。
B1 adjective /ˈɪnər/

inner

内面的
Meaning
Located inside or closer to the center; relating to one’s thoughts or feelings.
Example
She shared her inner thoughts with her best friend.
彼女は最良の友達に内面的な思いを共有しました。
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。
C2 verb /ɪnˈveɪɡəl/

inveigle

誘惑する
Meaning
To persuade someone to do something by deception or flattery.
Example
She inveigled him into signing the contract.
彼女は彼に契約書に署名させた。
C2 adjective /ˌɪnˈekspɜːrt/

inexpert

未熟な
Meaning
not skilled or experienced; lacking expertise
Example
The inexpert handling of the machine caused several mistakes.
機械の未熟な扱いがいくつかのミスを引き起こした。
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。
B2 noun ˌɪn.stəˈleɪ.ʃən

installation

インストール
Meaning
The action or process of installing someone or something, or of being installed.
Example
The installation of the submarine cable is almost complete.
海底ケーブルのインストールはほぼ完了しています。
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 verb /ɪnˈkɜːr/

incur

負う
Meaning
To bring upon oneself something undesirable, usually as a result of actions.
Example
He incurred a fine for parking in the wrong place.
彼は間違った場所に駐車して罰金を科せられた。
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。
C2 adjective /ˈɪn.dɪ.dʒənt/

indigent

困窮
Meaning
lacking the necessities of life due to poverty; very poor
Example
The hospital offers free care to indigent patients.
病院は困窮した患者に無料でケアを提供しています。
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。
C2 adjective ɪnˈfiː.zə.bəl

infeasible

不可能
Meaning
Not possible to do easily or conveniently; impracticable.
Example
Restoring the forest may become infeasible if destruction continues.
森林の回復は、破壊が続くと不可能になる可能性があります。
C1 noun /ˈɪmɪnəns/

imminence

差し迫り、間近な状態
Meaning
the state of being about to happen
Example
The imminence of the storm forced people to take shelter.
嵐の差し迫りが人々を避難させることを強制した。
A2 adjective/noun /ˈɪndiən/

indian

インディアンの
Meaning
Relating to India, its people, or their culture.
Example
She loves Indian food, especially biryani.
彼女はインディアンの料理が好きで、特にビリヤニが好きです。
B2 verb /ɪnˈhæbɪt/

inhabit

住む
Meaning
to live in; to occupy as a dwelling
Example
Many animals inhabit the forest.
多くの動物が森に住んでいます。
C2 adjective /ɪˈrɛfrəɡəbəl/

irrefragable

反論できない
Meaning
Impossible to refute, deny, or break
Example
The lawyer presented irrefragable evidence that proved his client’s innocence.
弁護士は彼のクライアントの無実を証明する反論できない証拠を提示しました。
C1 adjective /ɪnˈdɪɡnənt/

indignant

憤慨した
Meaning
Feeling or showing anger at something considered unfair or unjust.
Example
She was indignant when accused of cheating.
彼女は不正行為を非難されたとき、憤慨していた。
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 adjective /ɪnˈstrʌkʃənəl/

instructional

教育的な
Meaning
providing knowledge or information; intended to teach
Example
The website offers many instructional videos for beginners.
このウェブサイトは初心者向けに多くの教育的なビデオを提供しています。
B2 verb /ɪmˈpoʊzd/

imposed

課す
Meaning
forced something to be accepted or put in place
Example
The government imposed new regulations on the industry.
政府は産業に新しい規制を課した。
C2 verb /aɪˈtɪnəˌreɪt/

itinerate

旅行する
Meaning
To travel from place to place, usually for the purpose of work or preaching.
Example
The missionary itinerated throughout the region to spread the message.
伝道師は地域を巡り、メッセージを広めました。
C1 noun /ˈɪn.tə.mə.si/

Intimacy

親密さ; 親しみ
Meaning
close familiarity or friendship; closeness; a private cozy atmosphere
Example
The couple valued the emotional intimacy they shared more than material possessions.
そのカップルは物質的な所有物よりも、共有した感情的な親密さを大切にしていました。
C2 noun /ɪnˈtɛɡ.jʊ.mənt/

integument

外皮
Meaning
A natural outer covering, such as skin, shell, or rind.
Example
The snake sheds its integument as it grows.
ヘビは成長するにつれて外皮を脱ぎます。
B1 noun /ɪnˈʃʊərəns/

insurance

保険
Meaning
An arrangement by which a company provides compensation for loss, damage, or illness in return for a premium.
Example
He bought health insurance to cover medical expenses.
彼は医療費をカバーするために健康保険に加入しました。
B1 adjective /ɪnˈtɜːrnəl/

internal

内部
Meaning
situated inside; relating to the inside or inner part of something
Example
The company is conducting an internal audit this month.
その会社は今月内部監査を行っています。
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 verb /ɪnˈfætʃueɪt/

infatuate

夢中にさせる
Meaning
to inspire with an intense but short-lived passion or admiration
Example
He was infatuated with her beauty.
彼は彼女の美しさに夢中でした。
C2 adjective /ˌɪndɪˈsɒljʊbl/

indissoluble

解消できない
Meaning
Unable to be destroyed, broken, or dissolved.
Example
Marriage was once considered an indissoluble bond.
結婚はかつて解消できない絆と見なされていました。
B2 noun /ˈɪnstɪŋkt/

instinct

本能
Meaning
A natural way of behaving or reacting that does not require learning.
Example
Birds build nests by instinct.
鳥は本能で巣を作ります。
C2 verb /ɪnˈɡrɑːft/

ingraft

根付ける
Meaning
To implant or fix deeply, often used in the sense of grafting an idea or quality.
Example
The teacher tried to ingraft good manners in the students.
先生は生徒たちに良いマナーを根付かせようとした。
C2 verb /ɪˈreɪdieɪt/

irradiate

照射する
Meaning
to shine light on something; to expose to radiation; to illuminate or brighten
Example
The scientist used a lamp to irradiate the sample.
科学者はランプを使ってサンプルを照射しました。
B2 noun /ɪˈluː.ʒən/

Illusion

幻想
Meaning
a thing that is or is likely to be wrongly perceived or interpreted; a false idea or belief
Example
The magician created a spectacular illusion that made the elephant appear to vanish.
魔術師は壮観な幻想を作り、象が消えるように見えました。
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。
B2 verb /ɪnˈsɜːrt/

insert

挿入する
Meaning
to put or place something into something else
Example
Please insert the key into the lock.
鍵をロックに挿入してください。
C1 verb /ɪnˈklaɪn/

incline

傾く
Meaning
to feel willing or favorably disposed toward something; to bend or tilt
Example
She is inclined to agree with the proposal.
彼女は提案に賛成する傾向があります。
C2 adjective /aɪˈtɪnərənt/

itinerant

旅する
Meaning
Traveling from place to place, especially for work or duty.
Example
The itinerant teacher moved from village to village to educate children.
その旅する教師は村から村へと移動して子供たちに教育をしていました。
A2 adjective /ɪmˈpɑːsəbl/

impossible

不可能
Meaning
not able to occur, exist, or be done
Example
It is impossible to finish this work in one day.
この仕事を1日で終わらせるのは不可能です。
B2 noun /ɪnˈtɪəriər/

interior

インテリア
Meaning
the inside part of something; inner area of a place or object
Example
The interior of the hotel was beautifully decorated.
ホテルのインテリアは美しく装飾されていました。
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。
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 /ɪˈrɛpərəbəl/

Irreparable

修復不可能
Meaning
impossible to repair or fix; permanent damage that cannot be undone
Example
The accident caused irreparable damage to his spine.
その事故は彼の背骨に修復不可能な損傷を与えました。
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, noun /ɪnˈdɪkətɪv/

indicative

指示的
Meaning
Serving as a sign or expression of something; in grammar, a mood used to make factual statements.
Example
His tone was indicative of his frustration.
彼のトーンは彼のフラストレーションを示していた。
C2 noun /ɪˈreɪdiəns/

irradiance

放射輝度
Meaning
the quality of shining brightly; the intensity of light falling on a surface
Example
The irradiance of the sun at noon was overwhelming.
正午の太陽の放射輝度は圧倒的でした。
C1 verb /ɪnˈterəˌɡeɪt/

interrogate

尋問する
Meaning
to ask someone questions in a thorough and formal way; to question intensively
Example
The police interrogated the suspect for hours.
警察は容疑者を何時間も尋問した。
C2 noun /ɪmˌprɒb.əˈbɪl.ə.ti/

Improbability

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

infect

感染させる
Meaning
To contaminate with a disease-causing organism.
Example
The virus can infect healthy people quickly.
ウイルスは健康な人々を迅速に感染させることができます。
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。
C2 adjective /ˌɪnsəˈpɔːrtəbl̩/

insupportable

耐えられない
Meaning
Too extreme or difficult to be endured.
Example
The heat was insupportable during the long journey.
長い旅の間、暑さは耐えられなかった。
C2 adjective /ˌɪnkɔːrˈpɔːriəl/

incorporeal

無形
Meaning
lacking a physical body; not composed of matter; intangible
Example
Ghosts are often described as incorporeal beings.
ゴーストはしばしば無形の存在として描かれます。
C1 noun /ˈɪn.fən.tri/

Infantry

歩兵
Meaning
soldiers marching or fighting on foot; foot soldiers collectively
Example
The infantry advanced across the battlefield on foot.
歩兵は戦場を徒歩で進んだ。
C1 noun /ɪnˈsæn.ə.ti/

Insanity

狂気; 精神疾患
Meaning
the state of being seriously mentally ill; extreme foolishness or irrationality
Example
The defense lawyer argued that his client was not guilty by reason of insanity.
弁護人は、被告人が狂気によって無罪であると主張した。
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。
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。
C2 adjective /ˌɪnɔːˈspɪʃəs/

Inauspicious

不吉
Meaning
unlucky; showing signs that future success is unlikely; unfavorable
Example
The dark clouds seemed inauspicious for the wedding.
暗い雲は結婚式にとって不吉に思えた。
C1 verb /ɪnˈskraɪb/

inscribe

刻む
Meaning
to write or carve words or symbols on a surface
Example
They inscribed her name on the trophy.
彼らはトロフィーに彼女の名前を刻みました。
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。
B1 verb /ɪnˈtend/

intend

意図する
Meaning
to plan or have in mind as a purpose; to mean
Example
I intend to finish this project by tomorrow.
私はこのプロジェクトを明日までに終わらせるつもりです。
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。
C1 adjective /ɪmˈpɛn.ɪ.trə.bəl/

impenetrable

Meaning
Impossible to pass through or enter; impossible to understand.
Example
The dense forest was nearly impenetrable.
B1 verb /ɪnˈvɛs.tɪ.ɡeɪt/

investigate

調査する
Meaning
to carry out a systematic inquiry to discover facts or information
Example
The police will investigate the incident thoroughly.
警察は事件を徹底的に調査するでしょう。
C2 adjective /ˌɪrɪˈkɒnsɪləbl/

irreconcilable

和解できない
Meaning
impossible to make compatible or bring into harmony; unable to resolve differences
Example
The couple separated due to irreconcilable differences.
そのカップルは和解できない違いのために別れました。
B2 noun /ˈɪnˌsaɪt/

insight

洞察力
Meaning
The ability to understand the true nature of something; deep understanding.
Example
Her insight into human behavior made her a successful psychologist.
彼女の人間行動に対する洞察力は、彼女を成功した心理学者にした。
B1 noun /ɪnˈstrʌkʃənz/

instructions

指示
Meaning
Detailed information on how something should be done or operated.
Example
Please follow the instructions on the box.
箱に書かれた指示に従ってください。
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 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。
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 /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。
C1 noun /ɪnˈædɪkwəsi/

inadequacy

不十分さ
Meaning
lack of sufficient ability, quality, or strength; a feeling of not being good enough
Example
She struggled with feelings of inadequacy at work despite her strong qualifications.
十分な資格があるにもかかわらず、彼女は職場で不十分さを感じていた。
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。
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 /ɪˈmoʊbəl/

immobile

動けない
Meaning
unable to move or be moved
Example
After the accident, he was immobile for weeks.
事故の後、彼は数週間動けなかった。
C2 verb /ˈɪntərˌdɪkt/

interdict

禁じる
Meaning
to prohibit or forbid something by authoritative order, often by law or decree
Example
The court moved to interdict the sale of the illegal goods.
裁判所は違法な商品の販売を禁じることを決定しました。
C1 verb /ɪmˈpɛl/

impel

Meaning
to drive, force, or urge someone to do something
Example
Her curiosity impelled her to open the mysterious box.
C2 noun /ˈɪntərˌveɪl/

intervale

川沿いの低地、通常は肥沃で平坦
Meaning
A low-lying tract of land along a river, usually fertile and flat.
Example
The farmers cultivated crops on the lush intervale by the river.
農民たちは川沿いの肥沃な土地で作物を育てた。
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 /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。
B2 noun, verb /ɪntʃ/

inch

インチ / ゆっくり動く
Meaning
A unit of length equal to 2.54 centimeters; or to move slowly and carefully in small amounts.
Example
She inched closer to the edge of the stage.
彼女はステージの端にゆっくり近づいた。
C1 verb /ɪnˈdʌkt/

induct

Meaning
to formally admit someone into a position, organization, or office
Example
She was inducted into the university's honor society.