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B1 verb /ˈdɛmənˌstreɪt/

demonstrate

示す
Meaning
to clearly show or prove something through evidence, explanation, or action
Example
The teacher demonstrated the experiment to the class.
先生はクラスに実験をデモンストレートしました。
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.
B2 adjective /dɪˈzæs.trəs/

Disastrous

壊滅的な
Meaning
extremely bad or unsuccessful; causing great damage
Example
The hurricane had disastrous effects on the city.
ハリケーンは街に壊滅的な影響を与えました。
C1 noun /daɪˈsɛkʃən/

dissection

解剖
Meaning
the act of cutting apart or analyzing something in detail, especially a body or structure
Example
The dissection of the specimen revealed important details about its structure.
標本の解剖はその構造に関する重要な詳細を明らかにした。
C2 noun /dɪˈsɛnʃən/

dissension

意見の相違
Meaning
Strong disagreement or difference of opinion, especially leading to discord within a group.
Example
The meeting ended in dissension among the committee members.
会議は委員会メンバー間の意見の相違で終了しました。
B1 noun /ˌdɛfɪˈnɪʃən/

definition

定義
Meaning
a statement that explains the meaning of a word or concept
Example
The dictionary gives a clear definition of the word.
辞書はその言葉の明確な定義を示します。
C1 verb /dɪˈsɛm.ɪ.neɪt/

disseminate

普及する
Meaning
To spread or give out something, especially news, information, ideas, etc., to a lot of people.
Example
Social media helps to disseminate information quickly.
ソーシャルメディアは情報を迅速に普及するのに役立ちます。
B2 verb /dɪsˈmɪs/

dismiss

解雇する, 却下する
Meaning
to remove someone from a job or position; to decide something is not important
Example
The manager dismissed the employee for being late too often.
マネージャーは遅刻が多すぎるため、従業員を解雇しました。
C2 verb /ˈdɛpjʊˌtaɪz/

deputize

副職に任命する
Meaning
To appoint someone as a deputy; to act as a substitute or representative.
Example
The sheriff decided to deputize several locals to help maintain order.
保安官は秩序を維持するために数人の地元の人々を副職に任命することを決定しました。
B2 verb /dɪˈspætʃ/

dispatch

送る
Meaning
to send off to a destination or for a purpose
Example
The company dispatched aid to the flood victims.
その会社は洪水の被害者に援助を発送しました。
C2 noun /draɪd roʊz ˈpɛtəlz/

Dried Rose Petals

乾燥ローズの花びら
Meaning
dehydrated petals from roses used for culinary and aromatic purposes
Example
The dessert was garnished with dried rose petals.
デザートは乾燥ローズの花びらで飾られていました。
B2 noun /ˌdɒkjʊmɛnˈteɪʃən/

documentation

ドキュメンテーション
Meaning
material that provides official information or evidence
Example
The documentation for the project is available for review.
プロジェクトのドキュメンテーションはレビューのために利用可能です。
C2 adjective /ˈdekərəs/

decorous

品位のある
Meaning
showing proper and polite behavior; marked by good taste
Example
The audience gave a decorous applause after the performance.
観客は公演後に品位のある拍手を送りました。
C2 verb /ˌdɪsɪnˈhɛrɪt/

disinherit

遺産を剥奪する
Meaning
to deprive someone, especially a child, of inheritance or right to property
Example
The father threatened to disinherit his son for his reckless actions.
父親は息子の無謀な行動のために遺産を剥奪すると脅した。
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。
B2 verb /dɪˈraɪv/

derive

導き出す
Meaning
To obtain something from a source.
Example
Many English words derive from Latin.
多くの英語の単語はラテン語から導き出される。
C2 adjective /ˈdɒdərɪŋ/

doddering

震えている / 弱い
Meaning
Weak, shaky, or unsteady, especially due to old age.
Example
The doddering professor struggled to climb the stairs.
ドダリング教授は階段を登るのに苦労していました。
C2 noun /daɪˈɡrɛʃən/

digression

逸脱
Meaning
A temporary departure from the main subject in speech or writing.
Example
Her story was full of interesting digressions.
彼女の話は面白い逸脱で満ちていました。
C2 noun /ˈdɛsɪkənt/

desiccant

乾燥剤
Meaning
a substance that absorbs moisture and keeps things dry
Example
Silica gel packets are commonly used as a desiccant in packaging.
シリカゲルのパケットは、パッケージングで乾燥剤として一般的に使用されます。
B2 noun /diːd/

Deed

行為; 偉業; 法的文書;
Meaning
an action that is performed intentionally or consciously; a legal document showing ownership
Example
His heroic deed saved the child from drowning in the river.
彼の英雄的な行為は子供を川で溺れさせないように救った。
B2 adjective /dɪˈfektɪv/

Defective

欠陥のある; 不完全な
Meaning
having faults or defects; imperfect
Example
The defective product was returned to the store.
欠陥のある製品は店に返品されました。
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 /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.
C2 noun /dɪˈstɛnʃən/

distention

膨張
Meaning
The state of being swollen due to internal pressure.
Example
The patient complained of abdominal pain and distention.
患者は腹痛と膨張感を訴えました。
C1 verb /diːˈhaɪdreɪt/

dehydrate

Meaning
to remove water from something; to lose water or body fluids
Example
Running in the heat can quickly dehydrate you.
B2 noun /ˈdæf.ə.dɪl/

Daffodil

スイセン
Meaning
A bright yellow spring flower with a trumpet-shaped center, symbolizing rebirth and new beginnings
Example
The daffodils bloomed early this spring in the meadow.
この春、スイセンは草原で早く咲きました。
C2 noun /ˌdɪləˈtænt/

dilettante

愛好家
Meaning
A person who takes up an art, activity, or subject merely for amusement, especially in a superficial way.
Example
He was dismissed as a dilettante in the art world because he lacked formal training.
彼は芸術界で愛好家として退けられました、なぜなら正式な訓練が不足していたからです。
B2 noun /duːm/

doom

運命
Meaning
A terrible fate, destruction, or unavoidable bad outcome.
Example
The ancient prophecy foretold the city’s doom.
古代の予言は都市の運命を予見していた。
B2 verb /dæʃ/

dash

Meaning
to move quickly and suddenly; to strike or break something violently
Example
She dashed across the street to catch the bus.
A2 adjective/adverb /ˈdeɪli/

daily

毎日の
Meaning
happening every day
Example
She reads the newspaper daily.
彼女は毎日新聞を読んでいます。
C2 adjective /dɪˈsɛnʃənt/

dissentient

反対意見を持つ人
Meaning
Expressing or holding opinions that are opposed to the majority or official view.
Example
Only a few dissentient voices were heard during the debate.
討論中に反対意見を持つ少数の声だけが聞こえました。
B2 noun /diːp siː/

deep sea

深海
Meaning
The deep parts of the sea or ocean, typically beyond the continental shelf.
Example
Many deep-sea creatures produce bioluminescence for survival.
多くの深海生物は生存のために生物発光を生成します。
C2 noun /dɪˈstreɪnər/

distrainor

財産差し押さえ人
Meaning
a person, usually a landlord, who seizes another's property for unpaid debt or rent
Example
The distrainor took possession of the tenant's car until the debt was cleared.
ディストレイナーは、借金が清算されるまで、賃借人の車を押収しました。
B1 verb /dɪˈleɪ/

delay

遅延
Meaning
to make something happen later than planned
Example
The flight was delayed due to bad weather.
悪天候のため、飛行機が遅れました。
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。
B2 noun daɪˈlem.ə

dilemma

ジレンマ, 困難な選択
Meaning
A situation in which a difficult choice has to be made between two or more alternatives.
Example
She faced a moral dilemma at work.
彼女は職場で道徳的なジレンマに直面していた。
B2 adjective /ˈdɪl.ɪ.dʒənt/

Diligent

勤勉な
Meaning
hardworking and careful; showing persistent effort
Example
She is a diligent student who studies every day.
彼女は毎日勉強している勤勉な学生です。
C2 verb /dɪˈspɔɪl/

despoil

略奪する
Meaning
To steal or violently remove valuable possessions from a place.
Example
The invaders despoiled the village during the war.
侵略者は戦争中に村を略奪しました。
C1 noun /ˈdeɪ.ə.ti/

deity

神
Meaning
a god or goddess
Example
The temple is dedicated to a Hindu deity.
その寺院はヒンドゥー教の神に捧げられています。
A2 noun /dɪˈzɜːrt/

dessert

デザート
Meaning
the sweet course eaten at the end of a meal
Example
We had ice cream for dessert after dinner.
夕食後にデザートとしてアイスクリームを食べました。
B2 noun /ˈdɛltə/

delta

デルタ
Meaning
A landform at the mouth of a river where it splits into several outlets.
Example
The Nile Delta is one of the most fertile regions in Egypt.
ナイル川デルタはエジプトで最も肥沃な地域の1つです。
B2 noun /ˈdʌmi/

dummy

ダミー / バカな人
Meaning
a model or replica of a human used for practice, display, or testing; also a term for a foolish person
Example
The tailor used a dummy to display the dress.
仕立て屋はドレスを展示するためにダミーを使った。
C1 adjective /diːˈsɛntrəlaɪzd/

decentralized

分散型
Meaning
Controlled by several local offices or authorities rather than one single one.
Example
The decentralized system allowed for more control at local levels.
分散型システムは、ローカルレベルでのより多くの制御を可能にしました。
B1 adjective dəˈmes.tɪk

domestic

国内の
Meaning
Existing or occurring inside a particular country; not foreign or international.
Example
Domestic investments stabilize the economy.
国内投資は経済を安定させる。
C1 adjective /dɪˈsperɪŋ/

Despairing

絶望的な
Meaning
feeling hopeless; in despair
Example
She felt despairing after losing her job.
彼女は仕事を失った後、絶望的な気持ちだった。
C2 adjective /ˈdɪlətɔːri/

dilatory

遅延の
Meaning
Tending to cause delay; slow to act.
Example
The committee was criticized for its dilatory response to the crisis.
委員会は危機に対するその遅延反応で批判されました。
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。
C2 verb /dɪsˈkʌmfɪt/

discomfit

困惑させる
Meaning
to make someone feel uneasy, embarrassed, or confused
Example
The interviewer’s tough questions discomfited the candidate.
インタビュアーの厳しい質問が候補者を困惑させた。
B2 adverb /ˈden.sli/

densely

密に
Meaning
In a closely compacted or crowded manner.
Example
The area is densely covered with trees.
その地域は密に木々で覆われています。
B1 adjective /drəˈmæt.ɪk/

Dramatic

ドラマチック; 突然で驚くべき; 興奮させると印象的
Meaning
relating to drama; sudden and striking; exciting and impressive
Example
The dramatic sunset painted the sky in brilliant colors.
ドラマティックな夕焼けが空を明るい色で染めた。
A2 noun /dʌk/

Duck

アヒル
Meaning
a waterbird with webbed feet and a broad flat bill
Example
The duck swam gracefully across the lake.
そのカモは湖を優雅に泳いでいました。
C1 verb /dɪˈluːd/

delude

だます
Meaning
To mislead someone into believing something that is not true.
Example
He deluded himself into thinking he could win the race without training.
彼は訓練なしでレースに勝てると思い込み、自分をだました。
C1 adjective daɪˈvɜː.dʒənt

divergent

異なる
Meaning
Tending to be different or develop in different directions
Example
Divergent policies create challenges in collaboration.
異なる政策は協力に挑戦を生み出します。
C2 verb /dɪsˈɡɔːrdʒ/

disgorge

嘔吐, 排出
Meaning
to discharge or pour out; to vomit; to give up reluctantly
Example
The broken pipe disgorged water all over the floor.
壊れたパイプが床全体に水を吐き出しました。
C2 noun /djuːˈplɪsɪti/

duplicity

二重性
Meaning
Deceitfulness or double-dealing; dishonesty.
Example
Her duplicity was revealed during the investigation.
調査中に彼女の二重性が明らかになった。
C1 verb /ˌdɪsəˈsɛmbəl/

disassemble

分解する
Meaning
To take apart something into its separate pieces.
Example
He had to disassemble the computer to repair it.
彼は修理のためにコンピュータを分解しなければならなかった。
B1 adverb /ˈdaʊnwədz/

Downwards

下向き
Meaning
towards a lower place or position; in a downward direction
Example
The ball rolled downwards along the slope.
ボールは坂を下向きに転がった。
A1 noun /ˈdɒktər/

doctor

医者
Meaning
A qualified medical professional who treats illnesses and injuries.
Example
The doctor prescribed medicine for the patient.
医者は患者に薬を処方しました。
B2 adjective /dɪˌveləpˈmentl/

developmental

発展的
Meaning
relating to the process of growth or progress
Example
Early childhood is a crucial developmental stage for learning.
幼児期は学習にとって重要な発展的段階です。
B1 verb /ˌdɪsəˈpɔɪnt/

disappoint

失望させる
Meaning
to fail to fulfill the hopes or expectations of someone; to make someone feel sad or displeased
Example
I hope I won't disappoint you with my performance.
私はパフォーマンスであなたを失望させたくない。
B2 noun /dɪˈvoʊ.ʃən/

Devotion

献身; 忠誠; 熱意
Meaning
love, loyalty, or enthusiasm for a person, activity, or cause
Example
Her devotion to helping others made her a beloved figure in the community.
他人を助けることへの献身が、彼女をコミュニティで愛される存在にしました。
B2 verb /dɪˈskrɪmɪˌneɪt/

discriminate

Meaning
To treat someone unfairly based on race, gender, or other differences; or to recognize a distinction.
Example
The law prohibits employers from discriminating against women.
C2 verb /ˈdɪðər/

dither

Meaning
to be indecisive or unable to make a decision
Example
He dithered for hours before choosing a restaurant.
B1 verb /daɪv/

dive

飛び込む
Meaning
to plunge headfirst into water or another substance
Example
He decided to dive into the pool on a hot day.
彼は暑い日にプールにダイブすることに決めました。
B2 noun dɪˈplɔɪmənt

deployment

展開
Meaning
The action of bringing resources into effective action.
Example
The deployment of the new software was completed successfully.
新しいソフトウェアの展開は成功裏に完了しました。
A2 verb /ˌdɪsəˈpɪər/

disappear

消える
Meaning
to cease to be visible; to vanish
Example
The magician made the rabbit disappear.
マジシャンはウサギを消した。
B2 verb /dɪˈpɪkt/

depict

Meaning
to represent or show something in a picture, story, or other art form
Example
The painting depicts a beautiful sunset over the sea.
C1 adjective /dɪˈspɪkəbl/

despicable

卑劣な
Meaning
Deserving hatred and contempt; vile or shameful.
Example
His despicable actions shocked the entire community.
彼の卑劣な行動はコミュニティ全体を驚かせました。
C1 verb /dɪˈzɪst/

desist

Meaning
to stop doing something, especially an action considered wrong or undesirable
Example
The judge ordered the company to desist from unfair practices.
C2 noun /ˈduːti/

Dhuti

ドゥティ
Meaning
a traditional Indian garment for men consisting of a piece of unstitched cloth worn around the waist and legs
Example
The elderly man wore a white dhuti during the religious ceremony.
年配の男性は宗教的な儀式で白いドゥティを着ていた。
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。
B2 verb /ˈdɒmɪneɪt/

dominate

支配する
Meaning
to have power or control over something or someone
Example
The company dominates the smartphone market.
その会社はスマートフォン市場を支配しています。
C2 noun /ˈdændi/

dandy

外見と服装に過剰に気を使う男性
Meaning
a man who gives too much attention to his appearance and clothes
Example
The young dandy spent hours grooming himself before the party.
若いダンディはパーティーの前に何時間も自分を整えるのに費やした。
B2 adjective /dɪˈzɜːrtɪd/

deserted

人がいない
Meaning
Empty of people; abandoned.
Example
The village looked completely deserted after the storm.
嵐の後、その村は完全に人がいないように見えた。
C2 verb /dɪˈkænt/

decant

デキャンタ
Meaning
To pour liquid gently from one container into another, especially without disturbing the sediment.
Example
She carefully decanted the wine into a clean glass.
彼女は慎重にワインをきれいなグラスに注いだ。
C2 verb /ˌdɪskəmˈpoʊz/

discompose

動揺させる
Meaning
To disturb the order or calmness of something or someone.
Example
The unexpected question seemed to discompose her.
予期しない質問が彼女を動揺させたようだ。
B2 noun /ˈdoʊnər/

donor

ドナー
Meaning
A person who gives something, especially to a charity or cause.
Example
The donor contributed generously to the hospital’s new wing.
ドナーは病院の新しい翼に寛大に寄付しました。
C1 adjective /dɪˈsɪd.ju.əs/

deciduous

落葉樹
Meaning
Referring to trees that shed their leaves seasonally, typically in autumn.
Example
Oak and maple trees are deciduous, shedding leaves in autumn.
オークとカエデの木は落葉樹で、秋に葉を落とします。
B1 noun /dɪˈbeɪt/

Debate

討論
Meaning
a formal discussion of opposing viewpoints; argument with reasoned points
Example
The political debate lasted for three hours with passionate arguments.
政治的な討論は3時間続き、情熱的な議論が交わされました。
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 noun /ˌdɛməˈlɪʃən/

demolition

解体
Meaning
the act or process of destroying a building or structure
Example
The demolition of the old factory took several weeks.
古い工場の解体には数週間かかりました。
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 /dɪsˈdʒɔɪntɪd/

disjointed

ばらばら
Meaning
Lacking order, coherence, or connection; disconnected.
Example
The movie felt disjointed and hard to follow.
映画はばらばらに感じ、追いかけるのが難しかった。
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。
C2 noun /dəˈkɔɪt/

Dacoit

盗賊
Meaning
a member of an armed gang of robbers; a bandit, especially in India and Myanmar
Example
The village was terrorized by a gang of dacoits who robbed travelers.
その村は、旅行者を強盗した強盗団によって恐怖に陥れられました。
B1 verb /dɪˈzɜːrv/

deserve

値する
Meaning
To be worthy of something, usually a reward or punishment.
Example
She worked hard and deserves recognition.
彼女は一生懸命働き、認められる価値がある。
C2 noun /ˈdɛntɪfrɪs/

dentifrice

歯磨き粉
Meaning
a substance such as powder, paste, or liquid used to clean teeth
Example
He bought a new herbal dentifrice from the pharmacy.
彼は薬局で新しいハーブの歯磨きを買った。
B2 adjective /dɪˈstɜː.bɪŋ/

disturbing

気になる
Meaning
causing anxiety, worry, or emotional distress
Example
The news about the accident was deeply disturbing.
事故のニュースは非常に気分を害するものでした。
C2 verb /dɪˈtruːd/

detrude

下または外に押し出す
Meaning
To thrust or force something downward or outward.
Example
The violent waves detruded rocks from the cliff.
激しい波は崖から岩を押し出しました。
B2 noun /dʌv/

Dove

鳩
Meaning
a small, gentle bird with soft cooing sounds, often white and symbolizing peace
Example
The white dove flew peacefully across the blue sky.
白い鳩は青い空を平和に飛んでいた。
C2 noun /dɪˈprævɪti/

depravity

堕落
Meaning
moral corruption; wickedness
Example
The film portrays the moral depravity of a corrupt society.
その映画は腐敗した社会の道徳的堕落を描いています。
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。
B2 noun ˌdedɪˈkeɪʃn

dedication

献身
Meaning
The quality of being dedicated or committed to a task or purpose; devotion.
Example
His dedication laid the foundation of Indian science.
彼の献身はインディアの科学の基盤を築いた。
A2 verb /dɪsˈkʌvər/

discover

発見する
Meaning
to find something for the first time
Example
Scientists discovered a new planet last year.
科学者たちは昨年新しい惑星を発見しました。
C1 noun /dɪˈsaɪ.pəl/

Disciple

弟子; 信者
Meaning
a follower and student of a teacher, leader, or philosopher; devoted follower
Example
The famous philosopher had many disciples who spread his teachings worldwide.
その有名な哲学者には多くの弟子がいて、彼の教えを世界中に広めました。
C2 noun /doʊlt/

dolt

ばか
Meaning
A stupid or slow-witted person.
Example
Only a dolt would believe such a story.
そんな話を信じるのはばかだけだ。
C2 noun /dɪˈkæmɪtər/

decameter

デカメートル
Meaning
A metric unit of length equal to ten meters.
Example
The field was measured in decameters for accuracy.
そのフィールドは正確さのためにデカメートルで測定されました。
B2 adjective daɪˈdʒes.tɪv

digestive

消化の
Meaning
Relating to the digestion of food.
Example
Digestive enzymes help break down food.
消化酵素は食べ物を分解するのを助けます。
C2 verb /diːˈfrɑːk/

defrock

神父の職を剥奪する
Meaning
to officially remove a priest or minister from their position and authority
Example
The church decided to defrock the priest after the scandal.
教会はスキャンダルの後、神父を職務停止にしました。
B2 noun /diˈoʊ.dər.ənt/

Deodorant

デオドラント
Meaning
a substance that removes or conceals unpleasant smells, especially bodily odors
Example
She applied deodorant before going to the gym to stay fresh during workout.
彼女はジムに行く前に、トレーニング中にさっぱりとした状態を保つためにデオドラントを塗りました。
C2 noun /ˈdɛswɪˌtuːd/

desuetude

廃止
Meaning
a state of disuse or inactivity
Example
The old law has fallen into desuetude.
古い法律は廃止されました。
B2 noun /ˈdɛsɪməl/

decimal

十進法
Meaning
A number system based on 10; a number expressed in the base-10 system.
Example
The number 0.75 is a decimal.
0.75は十進法の数です。
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。
C2 verb /ˈdʌmfaʊnd/

dumbfound

呆然とさせる
Meaning
to greatly astonish or shock someone so they are temporarily speechless
Example
The magician's trick dumbfounded the audience.
マジシャンの技は観客を呆然とさせた。
C1 verb /daɪˈluːt/

dilute

薄める
Meaning
To make a liquid thinner or weaker by adding water or another solvent.
Example
You should dilute the juice with water before serving it to children.
子供たちに出す前にジュースを水で薄めるべきです。
B1 noun /ˈdrɛsɪŋ/

dressing

ドレッシング / 調味料の混合物
Meaning
a sauce for salads; or material used to cover a wound
Example
She prepared a delicious salad with Italian dressing.
彼女はイタリアンドレッシングで美味しいサラダを作った。
B1 verb/noun /ˈdiːkriːs/ (noun), /dɪˈkriːs/ (verb)

decrease

Meaning
To become or make something smaller or fewer in number, amount, or degree.
Example
The population of the town has decreased over the years.
C1 adjective /ˈdeɪnti/

dainty

優雅で可愛らしい
Meaning
Delicately small, pretty, and often considered elegant.
Example
She wore a dainty necklace made of pearls.
彼女は真珠でできた繊細なネックレスをしていました。
B1 adjective /ˌdɪs.əˈpɔɪn.tɪd/

Disappointed

がっかり
Meaning
sad because something has not happened or is not as good as expected
Example
She was disappointed with her exam results.
彼女は試験の結果にがっかりしていた。
B2 adjective /dɪˈskriːt/

discreet

慎重な
Meaning
careful and prudent in one's speech or actions, especially to keep something confidential or avoid embarrassment
Example
She was discreet about the details of their conversation.
彼女は彼らの会話の詳細について慎重でした。
B2 verb /ˈdɑːrkən/

darken

暗くする
Meaning
to make or become dark; to reduce brightness or light
Example
The clouds began to darken the sky before the storm.
嵐の前に雲が空を暗くし始めた。
B2 adjective /dɪˈskʌr.ɪ.dʒɪŋ/

Discouraging

落胆させる
Meaning
making someone feel less confident or enthusiastic about doing something
Example
The coach's discouraging words affected the team's morale.
コーチの落胆させる言葉は、チームの士気に影響を与えました。
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。
C2 verb /ˈdɒɡmətaɪz/

dogmatize

ドグマ化する
Meaning
To state opinions or beliefs as if they were absolute truths.
Example
The professor tended to dogmatize on political issues.
その教授は政治的な問題でドグマタイズする傾向があった。
C1 noun /ˈdrʌdʒəri/

drudgery

退屈で骨の折れる仕事
Meaning
Hard, menial, or dull work.
Example
She wanted to escape the drudgery of her daily routine.
彼女は日常の退屈なルーチンから抜け出したかった。
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 adjective /ˌdɪsɪnˈdʒɛnjʊəs/

disingenuous

不誠実な
Meaning
not candid or sincere; giving a false appearance of honesty or openness
Example
She gave a disingenuous excuse for missing the meeting.
彼女は会議に出席しないために不誠実な言い訳をしました。
C2 verb /deɪn/

deign

自分の尊厳を損ねて何かをする
Meaning
to do something considered beneath one's dignity
Example
The king did not deign to reply to the commoner.
王は平民に返答することをしなかった。
B2 noun/verb /dɪˈspjuːt/

dispute

争い, 論争
Meaning
a disagreement or argument about something important
Example
The two countries are in dispute over the border issue.
二国間で国境問題について争いが続いています。
A2 adjective /duː/

Due

期日; 予想される; 計画された
Meaning
owed as a debt; expected at a certain time; scheduled
Example
The assignment is due tomorrow.
課題は明日締め切りです。
C2 noun /ˌdaɪvəˈɡeɪʃən/

divagation

脱線
Meaning
digression; wandering from a path or subject
Example
His lecture was full of divagation, making it hard to follow the main point.
彼の講義は脱線だらけで、主なポイントを追うのが難しかった。