demonstrable
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C1 adjective /dɪˈmɒnstrəbl/

demonstrable

証明可能
Meaning
clearly able to be shown or proven
Example
There was demonstrable evidence that he was innocent.
彼が無罪であることを示す証明可能な証拠がありました。
C1 verb /dɪˈpliːt/

deplete

使い果たす
Meaning
to reduce the quantity or supply of something
Example
The long war has depleted the country's resources.
長引く戦争で国の資源は枯渇した。
C1 verb dɪˈsɜːn

discern

識別する
Meaning
To perceive or recognize something; to distinguish with difficulty by sight or with the other senses.
Example
He could barely discern the distant figure in the fog.
彼は霧の中で遠くの姿をほとんど識別できなかった。
C1 verb /ˈdæŋɡəl/

dangle

ぶら下がる
Meaning
to hang loosely or swing freely
Example
The keys dangled from his belt.
鍵がベルトからぶら下がっていました。
C1 noun /dɪˈstɔːrʃən/

distortion

歪曲、誤った提示
Meaning
the action of twisting, changing, or misrepresenting the shape, sound, or truth of something
Example
There was a distortion in the radio signal.
ラジオ信号に歪曲がありました。
C1 noun /dɪˈspɜːrʒən/

dispersion

分散
Meaning
The action or process of distributing things or people over a wide area.
Example
The dispersion of seeds by the wind helps plants reproduce.
風による種子の散布は、植物の繁殖を助けます。
C1 verb /ˈduːdəl/

doodle

Meaning
To draw or scribble absentmindedly, often while thinking about something else.
Example
She doodled flowers in the corner of her notebook during class.
C1 adjective /ˈdestatəʊt/

Destitute

困窮した; 貧しい; 財産もお金もない
Meaning
extremely poor; without money or possessions
Example
Many families became destitute after the economic collapse.
経済崩壊後、多くの家族は困窮しました。
C1 adjective /dɪˈfʌŋkt/

defunct

営業停止、廃止
Meaning
No longer existing, operating, or functioning.
Example
The company became defunct after the financial crisis.
その会社は金融危機の後で廃業しました。
C1 noun dɪˌzɝː.t̬ə.fɪˈkeɪ.ʃən

desertification

砂漠化
Meaning
The process by which fertile land becomes desert, typically as a result of drought, deforestation, or inappropriate agriculture.
Example
Deforestation accelerates desertification.
森林伐採は砂漠化を加速させます。
C1 noun /ˈdɛspɒt/

despot

暴君
Meaning
a ruler with absolute power, often ruling in a cruel or oppressive way
Example
The despot ruled the nation with fear and violence.
暴君は恐怖と暴力で国を支配した。
C1 noun /djuːˈɛt/

duet

デュエット
Meaning
a musical performance by two singers or instrumentalists
Example
They sang a beautiful duet together on stage.
彼らはステージで一緒に美しいデュエットを歌った。
C1 verb ˈdwɪn.dl

dwindle

減少する
Meaning
To diminish gradually in size, amount, or strength; to become progressively smaller.
Example
His savings dwindled due to unexpected expenses.
予期しない支出のため、彼の貯金は減少しました。
C1 noun dɪˈskrep.ən.siz

discrepancies

不一致
Meaning
Differences between things that should be the same
Example
Discrepancies in regulations delay progress.
規則の不一致が進行を遅らせている。
C1 verb dɪˈsaɪ.fɚ

decipher

解読する, 暗号を解く, 翻訳する
Meaning
To convert something written in code into normal language; to succeed in understanding the meaning of something.
Example
It took hours to decipher the ancient script.
古代の文字を解読するのに何時間もかかりました。
C1 verb /dɪˈvɒlv/

devolve

委譲する
Meaning
To pass power, responsibility, or duties to another person or group.
Example
The responsibility will devolve on the new manager.
責任は新しいマネージャーに委譲されます。
C1 adjective /dɪˈklærətɪv/

declarative

宣言的
Meaning
relating to a statement that declares something; in grammar, a sentence that makes a statement
Example
A declarative sentence simply states a fact or opinion.
宣言的な文は、単に事実や意見を述べるものです。
C1 noun /dɪˈsiːt/

Deceit

欺瞞; 詐欺; 嘘
Meaning
the action or practice of deceiving someone by concealing or misrepresenting the truth
Example
His deceit was discovered when the truth about his qualifications came to light.
彼の欺瞞は、彼の資格についての真実が明らかになったときに発覚しました。
C1 adjective /dɪˈfaɪənt/

Defiant

反抗的な; 逆らう
Meaning
boldly resistant or challenging; disobedient
Example
The defiant student refused to follow the rules.
その反抗的な学生はルールに従うことを拒否しました。
C1 noun /ˌdaɪəˈrɑːmə/

diorama

ジオラマ
Meaning
a three-dimensional model representing a scene, often with miniature figures
Example
The museum displayed a diorama of an ancient village.
博物館に古代の村のジオラマが展示されていました。
C1 verb /dɪˈflɛkt/

deflect

反らす / 避ける
Meaning
to cause something to change direction; to avoid answering directly
Example
The shield deflected the incoming arrow.
盾は飛んできた矢を反らした。
C1 noun/verb /dɪsˈdeɪn/

disdain

Meaning
The feeling that someone or something is unworthy of respect; to regard with contempt.
Example
She looked at the messy room with open disdain.
C1 verb /dɛlv/

delve

Meaning
To investigate deeply; to dig into a subject or area.
Example
The researcher delved into ancient manuscripts to find clues.
C1 adjective /daɪər/

Dire

深刻な; 緊急の; 恐ろしい
Meaning
extremely serious; urgent; terrible
Example
The country is facing a dire economic crisis.
その国は深刻な経済危機に直面している。
C1 adjective /dɪˈspɪrɪtɪd/

dispirited

落胆した
Meaning
Having lost enthusiasm, hope, or confidence; dejected.
Example
After losing the match, the team looked dispirited.
試合に負けた後、チームは落胆して見えた。
C1 noun delˈteɪɪk ˈlændskeɪp

deltaic landscape

デルタ地形
Meaning
A geographical area formed by sediment deposits at the mouth of a river, creating a triangular land formation.
Example
Bangladesh has a unique deltaic landscape.
バングラデシュにはユニークなデルタ地形があります。
C1 adjective /ˈdraʊ.zi/

Drowsy

眠い; 疲れた; 無気力な
Meaning
feeling sleepy and lethargic; half asleep; tired
Example
I felt drowsy after the heavy meal.
重い食事の後、眠気を感じました。
C1 verb /dɪˈraɪd/

deride

嘲笑する
Meaning
to mock or ridicule someone or something
Example
The critics derided the new movie for its poor script.
批評家たちはその新しい映画を悪い脚本のせいで嘲笑した。
C1 noun /ˈdɛdlɒk/

deadlock

行き詰まり
Meaning
a situation in which progress is impossible because of disagreement
Example
Negotiations reached a deadlock after neither side agreed to compromise.
交渉は双方が妥協に同意しなかったため行き詰まりました。
C1 verb /ˌdiː.kəmˈprɛs/

decompress

リラックスする
Meaning
To relax and recover from stress or pressure.
Example
Taking deep breaths helps to decompress after a stressful day.
深呼吸は、ストレスの多い一日後にリラックスするのに役立ちます。
C1 noun /ˈdæn.drʌf/

Dandruff

フケ
Meaning
small white or grey flakes of dead skin that form on the scalp and fall from the hair
Example
He used a special shampoo to treat his persistent dandruff problem.
彼は慢性的なフケの問題を治すために、特別なシャンプーを使った。
C1 verb /ˈdaʊn.pleɪ/

downplay

軽視する
Meaning
to make something seem less important than it really is
Example
The company tried to downplay the risks of the new product.
会社は新しい製品のリスクを軽視しようとしました。
C1 verb /dɪˈbeɪs/

debase

低下させる
Meaning
to reduce the quality, value, or dignity of something
Example
Corruption can debase the values of a society.
腐敗は社会の価値観を低下させる可能性があります。
C1 noun /dɪˈpɑːzətɔːri/

depository

預け場所, 保管所
Meaning
a place where things are stored or deposited, especially financial assets
Example
The national depository safeguards all government bonds.
国家のデポジトリはすべての政府債券を保護しています。
C1 noun ˌdiː.sen.trə.laɪˈzeɪ.ʃən

decentralization

分権
Meaning
The transfer of authority from central to local government.
Example
Decentralization promotes regional autonomy.
分権は地域の自立を促進します。
C1 verb /dɪsˈpærɪdʒ/

disparage

Meaning
to criticize someone or something in a way that shows a lack of respect
Example
It is unfair to disparage people for their opinions.
C1 noun daɪˈkɒtəmi

dichotomy

二項対立
Meaning
A division or contrast between two things that are or are represented as being opposed or entirely different.
Example
The dichotomy between tradition and modernity is often debated.
伝統と現代の二分法はよく議論されます。
C1 noun /ˈdrɪz.əl/

Drizzle

小雨
Meaning
light rain falling in very fine drops; a very light rainfall
Example
The gentle drizzle continued throughout the morning, making everything misty.
穏やかな小雨は朝の間中続き、すべてが霧のようになりました。
C1 noun /dɪsˈsɜːrvɪs/

disservice

害
Meaning
A harmful action; something that does damage rather than help.
Example
Spreading false information is a disservice to the community.
偽の情報を広めることは、コミュニティに害を与えることです。
C1 noun /ˌdɪspɛnˈseɪʃən/

dispensation

Meaning
An exemption from a rule or usual requirement; a system of order, government, or control.
Example
The school granted him a special dispensation to skip the exam due to illness.
C1 adjective ˌdet.rɪˈmen.təl

detrimental

有害な
Meaning
Tending to cause harm; damaging or harmful.
Example
Pollution has detrimental effects on fertility.
汚染は生殖能力に有害な影響を与えます。
C1 noun ˌdaɪvɜːsɪfɪˈkeɪʃən

diversification

多様化
Meaning
The practice of spreading investments across various assets or sectors to reduce risk.
Example
Diversification helps to reduce investment risk.
ダイバーシフィケーションは投資リスクを減らすのに役立ちます。
C1 adjective /ˈdesələt/

Desolate

荒涼; 孤独; 不毛
Meaning
deserted; lonely; barren
Example
The abandoned village looked desolate and empty.
放棄された村は荒涼として空っぽに見えた。
C1 verb /daɪˈvɜːrdʒ/

diverge

分岐する
Meaning
to separate and go in different directions; to differ
Example
The two paths diverge at the fork in the road.
二つの道は交差点で分かれる。
C1 verb /deɪz/

daze

Meaning
to stun or confuse someone temporarily with a shock or surprise
Example
The bright lights dazed the runners as they entered the stadium.
C1 noun dɪˌtɪə.ri.əˈreɪ.ʃən

deterioration

劣化
Meaning
The process of becoming progressively worse; decline in quality, condition, or strength.
Example
Poor maintenance leads to material deterioration.
不十分なメンテナンスは材料の劣化を引き起こす。
C1 adjective /dɪˈplɔːrəbl/

deplorable

ひどい
Meaning
deserving strong condemnation; shockingly bad in quality
Example
The refugees were living in deplorable conditions.
難民はひどい状況で生活していた。
C1 adjective deft

deft

器用
Meaning
Neatly skillful and quick in one's movements; dexterous and adroit.
Example
The artist's deft hands created a masterpiece.
アーティストの器用な手は傑作を作り出しました。
C1 noun /ˌdɪs.əˈreɪ/

disarray

混乱
Meaning
A state of disorganization or untidiness; confusion or disorder.
Example
His desk was in complete disarray.
彼の机は完全に混乱していました。
C1 noun /ˈdiːviəns/

deviance

逸脱
Meaning
Behavior that differs from accepted social or moral standards.
Example
The book studies deviance in urban youth culture.
その本は都市の若者文化における逸脱を研究しています。
C1 verb /dɪsˈlɒdʒ/

dislodge

追い出す
Meaning
To remove or force out from a position, especially one that is fixed or hard to move.
Example
The troops dislodged the enemy from the hill.
部隊は敵を丘から追い出した。
C1 adjective /dɪˈstrɔːt/

distraught

動揺した
Meaning
extremely upset and anxious, often to the point of being unable to think clearly
Example
She was distraught after losing her pet.
ペットを失った後、彼女は動揺していた。
C1 verb /dɪˈfaɪl/

defile

汚す
Meaning
to pollute, corrupt, or make dirty
Example
The river was defiled by industrial waste.
川は工業廃水によって汚された。
C1 noun ˈdɛtrɪ.mənt

detriment

損害、害、障害
Meaning
Harm, damage, impairment.
Example
Smoking is a detriment to health.
喫煙は健康に対するデトリメントです。
C1 noun /ˌdɪfəˈrɛnʃɪˈeɪʃən/

differentiation

差別化, 分化
Meaning
The action or process of differentiating or distinguishing between things.
Example
Differentiation from competitors can create a unique market position.
競合他社との差別化により、ユニークな市場ポジションを作り出すことができます。
C1 noun /dʌsk/

Dusk

夕暮れ; たそがれ
Meaning
the period of the day when daylight is fading; twilight
Example
They walked along the beach during dusk, watching the sunset.
彼らは夕暮れ時にビーチを歩きながら、日没を見ていました。
C1 noun /ˈdɛljuːdʒ/

deluge

洪水
Meaning
A severe flood; an overwhelming quantity of something.
Example
The town was hit by a deluge of rain in just a few hours.
その町は数時間で豪雨の洪水に襲われました。
C1 verb /ˌdɪsɪnˈɡeɪdʒ/

disengage

解放する
Meaning
To release or detach oneself from something; to withdraw.
Example
He tried to disengage from the heated argument.
彼は熱い議論から解放しようとした。
C1 noun /ˌdez.ɪɡˈneɪ.ʃən/

Designation

任命; 役職; 職位; ステータス
Meaning
the action of choosing someone for a position; a name, title, or official status
Example
His designation as team leader came with additional responsibilities and authority.
チームリーダーとしての彼の任命は、追加の責任と権限を伴っていました。
C1 noun /ˈdek.ə.dəns/

decadence

堕落
Meaning
Moral or cultural decline characterized by excessive indulgence in pleasure or luxury.
Example
The novel describes the decadence of the wealthy elite.
その小説は裕福なエリートの堕落を描いています。
C1 noun /ˌdep.rɪˈveɪ.ʃən/

deprivation

剥奪, 欠乏, 不足
Meaning
The damaging lack of material benefits considered to be basic necessities in a society.
Example
Sleep deprivation affects cognitive function.
睡眠不足は認知機能に影響を与えます。
C1 noun /daɪˈvɜː.dʒəns/

divergence

分岐
Meaning
The process or state of diverging; a difference or deviation between two or more things.
Example
The divergence in their opinions led to a heated debate.
彼らの意見の相違は激しい議論を引き起こしました。
C1 verb /dɪˈspɛns/

dispense

配布する
Meaning
To distribute or provide something, especially in portions.
Example
The machine dispenses clean drinking water.
その機械は清潔な飲料水を供給します。
C1 noun /dɪn/

din

騒音
Meaning
a loud, unpleasant, and prolonged noise
Example
The din of traffic outside made it hard to concentrate.
外の交通の騒音が集中するのを困難にしていた。
C1 noun /dɪˈfaɪəns/

defiance

反抗
Meaning
Open resistance or bold disobedience.
Example
The protest was an act of defiance against injustice.
その抗議は不正に対する反抗の行為でした。
C1 adjective /dɪˈbeɪst/

debased

劣化した
Meaning
having lost quality, value, or moral character
Example
The debased currency lost the trust of the people.
劣化した通貨は人々の信頼を失った。
C1 adjective /dɪˈreɪndʒd/

deranged

狂気
Meaning
mentally disturbed or insane; behaving irrationally
Example
The deranged man shouted nonsense in the street.
狂った男が街で無意味なことを叫んでいた。
C1 verb /daɪˈleɪt/

dilate

拡大する
Meaning
To make wider, larger, or more open.
Example
The doctor used drops to dilate the patient's pupils.
医者は患者の瞳孔を拡げるために点眼薬を使いました。
C1 verb /dɪˈfrɔːd/

defraud

詐欺
Meaning
to illegally take money or valuables from someone by deception
Example
The company was accused of trying to defraud investors.
その会社は投資家をだまそうとしたとして告発されました。
C1 verb /dɪsˈmæntəl/

dismantle

解体する
Meaning
to take apart; to remove or destroy the parts of
Example
Workers will dismantle the old bridge next month.
作業員たちは来月古い橋を解体します。
C1 noun /deɪˈtɒnt/

detente

緊張関係の緩和
Meaning
the easing of strained relations, especially between countries
Example
The treaty helped bring about a détente between the two nations.
その条約は、二国間の緊張関係を緩和するのに役立ちました。
C1 adjective /ˈdɒɡɪd/

dogged

執拗
Meaning
showing stubborn determination and persistence
Example
She succeeded through dogged determination.
彼女は執拗な決意で成功を収めました。
C1 noun/verb /dɪsˈkwaɪət/

disquiet

Meaning
A feeling of worry or unease; to make someone feel anxious or uneasy.
Example
The strange silence filled the room with disquiet.
C1 verb /dɪˈmiːn/

demean

侮辱する
Meaning
to cause someone to lose dignity or respect
Example
The manager demeaned his employees with rude remarks.
マネージャーは粗野なコメントで社員を侮辱しました。
C1 adjective /dɪˈmɒnstrətɪv/

demonstrative

表現的な
Meaning
openly showing feelings, especially affection or emotion
Example
She was very demonstrative with her affection towards her friends.
彼女は友達に対してとても表現的だった。
C1 noun /dɪˈprɛsənt/

depressant

抑制剤
Meaning
A drug that reduces functional or nervous activity in the body.
Example
Alcohol acts as a depressant on the central nervous system.
アルコールは中枢神経系に抑制剤として作用します。
C1 adjective /ˈdek.stər.əs/

dexterous

器用
Meaning
Showing or having skill, especially with the hands; mentally adroit and skillful.
Example
A dexterous programmer can write complex codes effortlessly.
器用なプログラマーは複雑なコードを楽々と書けます。
C1 noun /ˌdɪspəˈzɪʃən/

disposition

Meaning
A person's usual attitude or temperament; arrangement or tendency.
Example
She has a cheerful disposition despite the difficulties.
C1 adjective dɒɡˈmæt.ɪk

dogmatic

教条的
Meaning
Being inclined to lay down principles as incontrovertibly true; characterized by arrogant assertion of unproven principles.
Example
His dogmatic approach to politics made discussions difficult.
彼の教条的なアプローチは、議論を難しくしました。
C1 verb /dɪˈteɪn/

detain

Meaning
to keep someone from proceeding; to hold back, especially by official authority
Example
The police detained the suspect for questioning.
C1 adjective /dɪˈsɜːrnɪŋ/

discerning

鋭い
Meaning
having good judgment or insight; able to distinguish well
Example
He is a discerning reader who notices subtle details.
彼は鋭い読者で、微細な詳細に気づきます。
C1 noun ˈdɪl.ɪ.dʒəns

diligence

勤勉
Meaning
Careful and persistent work or effort.
Example
Success requires patience and diligence.
成功には忍耐と勤勉が必要です。
C1 noun /ˌdɛfəˈmeɪʃən/

defamation

名誉毀損
Meaning
the act of damaging someone's reputation by making false statements
Example
The newspaper was sued for defamation of character.
その新聞は名誉毀損で訴えられた。
C1 adjective /ˈdaʊ.ər/

dour

厳格
Meaning
relentlessly severe, stern, or gloomy in manner or appearance
Example
His dour expression made the meeting uncomfortable.
彼の厳格な表情は会議を不快にした。
C1 noun /ˌdɛtəˈneɪʃən/

detonation

爆発
Meaning
The act of exploding or causing something to explode.
Example
The sudden detonation shook the entire building.
突然の爆発が建物全体を揺さぶった。
C1 adjective /dɪˈlæpɪˌdeɪtɪd/

dilapidated

老朽化した
Meaning
Fallen into disrepair or ruin due to neglect or age.
Example
The family lived in a dilapidated house at the edge of town.
その家族は町の端にある老朽化した家に住んでいました。
C1 verb /dɪsˈoʊn/

disown

拒絶する
Meaning
to refuse to acknowledge or accept responsibility for someone or something
Example
He decided to disown his reckless brother.
彼は無謀な兄を拒絶する決断をしました。
C1 noun, adjective /dɪˈrɪvətɪv/

derivative

派生物
Meaning
Something that is based on another source; in math, a measure of how a function changes.
Example
The film was criticized for being too derivative of earlier works.
その映画は、前の作品を模倣しすぎて批判されました。
C1 adjective /dɪˈlɪriəs/

delirious

デリリアス
Meaning
in an extremely disturbed or excited state of mind, often due to illness or emotion
Example
He was delirious with fever and kept muttering nonsense.
彼は熱でデリリアスで、無意味なことを呟いていた。
C1 noun /ˈdæɡ.ər/

Dagger

短剣
Meaning
a short knife with a pointed blade used as a weapon
Example
The ancient warrior carried a silver dagger.
古代の戦士は銀の短剣を携えていた。
C1 noun /djuːn/

dune

砂丘
Meaning
A hill or ridge of sand formed by the wind, usually found in deserts or near beaches.
Example
The children played on the sand dune by the beach.
子供たちはビーチの砂丘で遊んでいました。
C1 noun /ˈdʊr.i.ən/

Durian

ドリアン
Meaning
a large spiky tropical fruit known for its strong smell and creamy custard-like flesh
Example
Durian is known as the king of fruits in Southeast Asia despite its pungent odor.
ドリアンは強い匂いにもかかわらず、東南アジアで果物の王として知られている。
C1 adjective dɪ ˈskrɛʃ.ən.er.i

discretionary

裁量の
Meaning
Available for use at the discretion of the user; not required or mandatory.
Example
He set aside some discretionary income for travel.
彼は旅行のためにいくらかの裁量所得を取っておいた。
C1 verb /dɪsˈpleɪs/

displace

置き換える
Meaning
to force someone or something out of their usual or original position; to replace or substitute
Example
The new technology will displace many traditional manufacturing jobs.
新しい技術は多くの伝統的な製造業の仕事を置き換えるでしょう。
C1 noun /ˌdiːˈmer.ɪt/

Demerit

欠点; 不利; 過ちや違反に対して与えられるマーク
Meaning
a fault or disadvantage; a mark given for a fault or offense
Example
The student received a demerit for arriving late to class repeatedly.
その生徒は繰り返し遅刻したため、デメリットを受けました。
C1 noun dɪˈfleɪʃən

deflation

デフレーション
Meaning
Reduction of the general level of prices in an economy.
Example
Deflation often leads to decreased consumer spending.
デフレーションはしばしば消費者の支出を減少させる。
C1 noun ˌdɪm.ɪˈnjuː.ʃən

diminution

減少
Meaning
A reduction in the size, extent, or importance of something; decrease.
Example
There has been a diminution in air pollution.
大気汚染の減少がありました。
C1 noun /diːˈkrɪp.ʃən/

decryption

復号
Meaning
The process of converting encrypted data back into its original form so it can be understood.
Example
Hackers attempted decryption of classified data.
ハッカーは分類されたデータの復号を試みました。
C1 noun /ˌdiː.viˈeɪ.ʃən/

Deviation

逸脱；定められたコースから外れること
Meaning
the action of departing from an established course; a departure from usual standards
Example
Any deviation from the established procedure must be reported immediately.
定められた手順からの逸脱は直ちに報告されなければなりません。
C1 noun /ˈdɪs.ə.nəns/

dissonance

不協和音
Meaning
Disagreement, lack of harmony, conflict between ideas or beliefs.
Example
The cultural dissonance created misunderstandings.
文化的な不協和音が誤解を生んだ。
C1 noun /dɪˈluːʒən/

delusion

錯覚
Meaning
A false belief or impression maintained despite being contradicted by reality.
Example
He lived under the delusion that he was invincible.
彼は自分が無敵だという錯覚の中で生きていた。
C1 adjective /ˈdæʃ.ɪŋ/

Dashing

魅力的; スタイリッシュ; 自信に満ちた;
Meaning
stylish and confident; lively and energetic; attractive and charming
Example
He looked dashing in his new suit.
彼は新しいスーツで魅力的に見えました。
C1 adjective /ˈdaʊn.kæst/

downcast

Meaning
feeling sad, dejected, or with lowered eyes
Example
He looked downcast after hearing the bad news.
C1 verb /dɪsˈpruːv/

disprove

反証する
Meaning
to show that something is false or wrong
Example
The scientist worked hard to disprove the old theory.
科学者は古い理論を反証するために一生懸命働いた。
C1 noun /ˈdeɪˌbreɪk/

daybreak

夜明け
Meaning
The time in the morning when daylight first appears; dawn.
Example
They set out on their journey at daybreak.
彼らは夜明けに旅を始めました。
C1 adjective /ˈdɛkədənt/

decadent

堕落的, 贅沢な
Meaning
Characterized by or reflecting a state of moral or cultural decline; excessively self-indulgent.
Example
The party was filled with decadent luxury and excess.
パーティーは堕落的な贅沢と過剰で満たされていました。
C1 noun /ˈdaɪhɑːrd/

diehard

Meaning
A person who strongly resists change and remains loyal to a belief or cause.
Example
He is a diehard fan of classic rock music.
C1 verb /dɪsˈbænd/

disband

解散する
Meaning
to break up and stop functioning as a group or organization
Example
The club decided to disband after twenty years of activity.
クラブは20年の活動後に解散することを決定した。
C1 verb diːˈsɛn.sɪ.taɪz

desensitize

脱感作
Meaning
To make someone less sensitive or reactive to something through repeated exposure.
Example
Constant exposure to violence can desensitize people.
継続的な暴力の露出は人々を鈍感にする可能性があります。
C1 verb ˈdiː.vi.eɪt

deviate

逸脱する
Meaning
To depart from an established course or normal pattern.
Example
He tends to deviate from the original plan.
彼は元の計画から外れる傾向がある。
C1 adjective /dɪˈmɛntɪd/

demented

狂った / 非理性的
Meaning
behaving irrationally due to mental illness or extreme excitement
Example
He looked demented after hearing the shocking news.
彼は衝撃的なニュースを聞いた後、正気を失ったように見えました。
C1 noun /dɪsˈɒn.ər/

Dishonour

不名誉
Meaning
a state of shame or disgrace; lack of honor or integrity; failure to fulfill obligations
Example
Breaking his promise brought dishonour to his name and family legacy.
約束を破ったことが彼の名前と家族の遺産に不名誉をもたらした。
C1 adjective /dɪˈspɜːrst/

dispersed

散らばった
Meaning
Scattered or spread across a wide area.
Example
The dispersed population made it difficult to provide public services.
散らばった人口は公共サービスの提供を困難にしました。
C1 noun ˌdɪs.æmˌbɪɡ.juˈeɪ.ʃən

disambiguation

曖昧さの解消
Meaning
The removal of ambiguity by making something clear and unambiguous.
Example
The AI system applies disambiguation to refine text understanding.
AIシステムはテキスト理解を精緻化するためにディスアンビギュエーションを適用します。
C1 noun /dɪˈten.ʃən/

Detention

停学; 拘留
Meaning
the action of detaining someone or being detained in official custody
Example
The student received detention for repeatedly disrupting the class.
生徒は繰り返しクラスを乱したため、停学を受けました。
C1 noun /ˌdɜːrməˈtɑːlədʒi/

dermatology

皮膚科学
Meaning
The branch of medicine concerned with the skin and its diseases.
Example
He studied dermatology at medical school.
彼は医学部で皮膚科学を学んだ。
C1 noun /dɪˈrɪʒən/

derision

嘲笑
Meaning
Contemptuous ridicule or mockery.
Example
His ideas were greeted with derision by the audience.
彼のアイデアは観客によって嘲笑された。
C1 adjective /dɪsˈkɔːrdənt/

discordant

不協和音
Meaning
disagreeing or clashing; harsh and jarring in sound
Example
The discordant notes of the band hurt our ears.
バンドの不協和音の音が私たちの耳を痛めました。
C1 noun /ˈdɔːrˌkiːpər/

doorkeeper

門番
Meaning
A person whose job is to guard or manage the entrance of a building or room.
Example
The doorkeeper checked everyone’s passes before they entered the hall.
ドアキーパーは皆がホールに入る前に通行証を確認した。
C1 verb /diːˈkoʊd/

decode

Meaning
to convert a coded message into a readable form; to interpret meaning
Example
The software can decode the hidden message within seconds.
C1 noun ˌdɛməˈɡræfɪk trænˈzɪʃən

demographic transition

人口転換
Meaning
A shift in population patterns from high birth and death rates to low birth and death rates as a country develops economically
Example
The demographic transition indicates a shift towards an aging society.
人口転換は高齢化社会への移行を示しています。