Riddle
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B2 noun /ˈrɪdəl/

Riddle

Meaning
a question or statement intentionally phrased so as to require ingenuity in ascertaining its answer or meaning; a puzzle
Example
The ancient riddle stumped all the scholars for years.
その古代の謎は何年もの間、すべての学者を困らせました。
C2 noun /ˈræbəl/

Rabble

群衆
Meaning
a disorderly crowd; the common people regarded as socially inferior
Example
The politician dismissed the protesters as mere rabble.
政治家は抗議者を単なる群衆として退けた。
B2 verb /rɪˈzɑlv/

resolve

解決する
Meaning
to solve a problem; to decide firmly
Example
The manager resolves the conflict between employees.
マネージャーは従業員間の対立を解決します。
C1 noun /ˈriːbeɪt/

rebate

リベート/払い戻し
Meaning
a partial refund given to someone who has paid too much money for something
Example
The store offered a rebate on bulk purchases.
その店は大量購入に対してリベートを提供しました。
B1 noun /ˈref.ər.əns/

Reference

参考文献
Meaning
the action of mentioning or alluding to something; a source of information
Example
Please provide references to support your research claims.
研究の主張を支持するために参考文献を提供してください。
C2 adjective /rəˈʃɛrʃ/

recherche

希少
Meaning
Rare, exotic, or obscure, often in a sophisticated or refined way.
Example
The gallery displayed many recherche artworks from unknown artists.
ギャラリーは、未知のアーティストによる多くの希少なアート作品を展示しました。
C2 noun /rɪˌdʒuːvəˈnɛsəns/

rejuvenescence

再生
Meaning
the action or process of becoming young or fresh again
Example
The forest showed signs of rejuvenescence after the rains.
雨の後、森は再生の兆しを見せました。
B1 noun /rɪˈtaɪə.mənt/

Retirement

退職
Meaning
the action or fact of leaving one's job and ceasing to work; the period of life after leaving work
Example
He is planning his retirement after 40 years of service.
彼は40年間の勤務の後、退職を計画しています。
C1 noun /rɪˈliːf treɪn/

Relief Train

救援列車
Meaning
a train that carries emergency supplies and aid to disaster-affected areas
Example
The relief train arrived with food and medical supplies for the flood victims.
救援列車は洪水の被害者のために食料と医療物資を運んできました。
B2 adverb /rɪˈlʌk.tənt.li/

Reluctantly

いやいや
Meaning
in an unwilling manner; with hesitation or resistance
Example
She reluctantly agreed to help with the project.
彼女はプロジェクトを手伝うことに渋々同意した。
B1 preposition /rɪˈɡɑrdɪŋ/

regarding

に関して
Meaning
concerning or relating to
Example
The decision regarding the meeting will be made tomorrow.
会議に関する決定は明日行われます。
B1 noun ˈreɪn.fɒr.ɪst

rainforest

熱帯雨林
Meaning
A luxuriant, dense forest rich in biodiversity, found typically in tropical areas with consistently heavy rainfall.
Example
The Amazon rainforest is home to millions of species.
アマゾンの熱帯雨林は数百万種の生物の家です。
A2 preposition /riː/

re

について
Meaning
concerning or about (used in formal letters or emails)
Example
The letter was sent re your recent application.
その手紙はあなたの最近の申請について送られました。
A1 verb /riːd/

read

読む
Meaning
to look at written words and understand their meaning
Example
I read books before going to bed.
私は寝る前に本を読みます。
C1 adjective ˈriːdʒən spəˈsɪfɪk

region-specific

地域特有
Meaning
Relating to or characteristic of a particular region or area.
Example
Climate change impacts are region-specific.
気候変動の影響は地域特有です。
A2 noun /rɒk/

rock

岩石
Meaning
a large, solid piece of mineral matter
Example
The mountain was made of solid rock.
その山は固い岩石でできていました。
C1 verb /ˈræʃənaɪz/

rationlize

合理化する
Meaning
to justify or explain something with logical reasons, even if not appropriate or true
Example
He tried to rationlize his mistake by blaming the system.
彼はシステムを責めて自分のミスを合理化しようとした。
B1 noun /ˈrʌnər/

runner

幸せ
Meaning
a person who runs, especially in races or for exercise
Example
The runner crossed the finish line with a big smile.
彼女は賞を受け取ったとき、幸せを隠せなかった。
C1 noun /rəˈviːn/

ravine

渓谷
Meaning
A deep, narrow valley with steep sides.
Example
The river carved a deep ravine through the mountains.
川は山々を通って深い渓谷を作り出した。
B2 verb /ˈrɛkən/

reckon

推測する
Meaning
To think, believe, or expect something; to calculate or estimate.
Example
I reckon it will rain later today.
今日は後で雨が降るだろうと思います。
C1 verb /rɪˈdʒuː.vɪ.neɪt/

rejuvenate

再生する
Meaning
To make or feel young, healthy, or energetic again.
Example
A vacation can rejuvenate the mind and body.
休暇は心と体を再生させることができます。
C1 noun /ˈrez.ɪ.dənt ˈkəʊ.ɔː.dɪ.neɪ.tər/

resident coordinator

居住者コーディネーター
Meaning
A local administrator or official who coordinates activities in a specific region.
Example
The resident coordinator welcomed all representatives.
居住者コーディネーターは全ての代表者を歓迎しました。
B1 noun /ruːt/

route

Meaning
a way or course taken to get from one place to another
Example
The best route to the airport is through the highway.
B1 noun riˈækʃən

reaction

反応
Meaning
An action performed or a feeling experienced in response to a situation or event.
Example
The arrests triggered a reaction.
逮捕は反応を引き起こしました。
C2 noun /ˈrɛdʒɪsaɪd/

regicide

王殺し
Meaning
the act of killing a king
Example
The conspirators were executed for committing regicide.
陰謀者たちは王殺しを犯したため、処刑されました。
B2 noun /ˈruːdnəs/

Rudeness

無礼
Meaning
the quality of being impolite, discourteous, or offensive in behavior or speech
Example
His rudeness shocked everyone at the dinner party.
彼の無礼さはディナーパーティーで皆を驚かせました。
B2 noun /ˈreb.əl/

Rebel

反逆者
Meaning
a person who resists authority or control
Example
The young rebel refused to follow the school rules.
その若い反逆者は学校の規則に従うことを拒否した。
C2 noun /ˈrɛkjʊzənt/

recusant

反抗者
Meaning
a person who refuses to submit to authority or comply with rules
Example
The recusant opposed the new law.
反抗者は新しい法律に反対しました。
B1 noun /rɪˈzɔː.sɪz/

resources

資源
Meaning
A stock or supply of money, materials, staff, and other assets.
Example
The region was rich in herbal resources.
その地域は薬草の資源が豊富でした。
B1 noun /rɪˈpɔːrtər/

reporter

レポーター
Meaning
a person who reports news or information
Example
The reporter interviewed several people at the scene.
レポーターは現場で数人にインタビューしました。
C1 verb /rɪˈkaʊnt/

recount

語る
Meaning
to narrate or tell the details of an event or experience
Example
She recounted her adventures during the summer trip.
彼女は夏の旅行中の冒険について語った。
B1 adjective /rɪˈtaɪərd/

Retired

引退した
Meaning
having left one's job and ceased to work; withdrawn from activity
Example
My retired grandfather enjoys gardening in his free time.
私の引退した祖父は自由な時間に園芸を楽しんでいます。
B2 noun /ˈræŋkɪŋ/

ranking

ランキング
Meaning
a position in a list or hierarchy, especially in terms of performance or importance
Example
His ranking in the competition improved after each round.
彼の競技でのランキングは、各ラウンド後に向上しました。
C1 verb /riˈdʒɔɪn/

rejoin

再参加する
Meaning
to join again or return to a group, place, or activity
Example
After a short break, she decided to rejoin the team.
短い休憩後、彼女はチームに再参加することに決めました。
C2 verb /ˌriː.kəˈnɔɪ.tər/

reconnoiter

偵察する
Meaning
to make a preliminary inspection or survey, especially of an area for military or strategic purposes
Example
The soldiers reconnoitered the area before advancing.
兵士たちは進軍する前にその地域を偵察しました。
C2 noun /rɪˌkrɪmɪˈneɪʃən/

recrimination

相互非難
Meaning
an accusation made in response to an accusation; mutual blaming
Example
The debate quickly descended into mutual recriminations.
討論はすぐに相互非難に陥った。
C1 verb /ˌriːˈkæst/

recast

再キャスティング
Meaning
To present or change something in a different form or style.
Example
The director decided to recast the role with a younger actor.
監督は役を若い俳優でリキャストすることに決めました。
B1 adjective /rɪˈleɪ.tɪd/

Related

関連; 結びついている
Meaning
connected; associated; having a connection or relationship
Example
These two problems are closely related to each other.
これらの二つの問題はお互いに密接に関連しています。
C2 noun /ˈrɪɡməˌroʊl/

rigmarole

面倒なこと
Meaning
a long, complicated, and confusing process or story
Example
Getting a visa was such a rigmarole of paperwork and interviews.
ビザを取得するのは、書類とインタビューの面倒なことだった。
B2 verb /rɪˈfaɪn/

refine

洗練する
Meaning
to improve by making small changes; to purify
Example
The chef refines the recipe to perfection.
シェフはレシピを完璧に洗練します。
C2 adjective /ˌriːkruːˈdɛsənt/

recrudescent

再発
Meaning
reviving or breaking out again after a period of abatement
Example
Recrudescent tensions threatened the fragile ceasefire.
再発した緊張が脆弱な停戦を脅かしました。
A2 noun rɪˈspɛkt

respect

尊敬
Meaning
A feeling of deep admiration for someone or something.
Example
We should show respect to the freedom fighters.
私たちは自由の戦士たちに尊敬を示すべきです。
C2 adjective /rɪˈflɛktɪbəl/

reflectible

反射可能
Meaning
capable of being reflected, as light or an image
Example
The surface of the lake is highly reflectible in the morning sun.
湖の表面は朝の太陽の下で非常に反射可能です。
B2 noun /ˈrem.ə.di/

Remedy

薬; 治療; 問題解決の手段
Meaning
a medicine or treatment for a disease; a solution to a problem
Example
This herbal remedy helps with headaches.
このハーブの薬は頭痛に効く。
A2 verb /riːˈsaɪ.kəl/

recycle

リサイクル
Meaning
to process used materials so they can be used again instead of being thrown away
Example
We should recycle paper and plastic to reduce waste.
私たちは廃棄物を減らすために紙とプラスチックをリサイクルするべきです。
C1 adjective /ˈrɛtɪsənt/

reticent

控えめ
Meaning
not revealing one's thoughts or feelings readily; reserved
Example
She was reticent about her personal life.
彼女は自分の個人的な生活について控えめでした。
C2 noun /ˈrɛkwiəm/

requiem

レクイエム
Meaning
A mass, music, or ceremony for the repose of the souls of the dead.
Example
The choir performed a requiem in memory of the late leader.
合唱団は故リーダーを記念してレクイエムを演奏しました。
B2 adjective rɪˈnaʊnd

renowned

著名
Meaning
Known or talked about by many people; famous.
Example
The renowned scientist led the reform panel.
その著名な科学者は改革パネルを指導しました。
B1 verb /rɪˈtaɪə/

retire

引退する
Meaning
to stop working after reaching a certain age or having completed a career
Example
She decided to retire after working for 40 years.
彼女は40年間働いた後、引退することに決めました。
C2 verb /ˈrævɪʃ/

ravish

魅了する
Meaning
To fill with intense delight; to captivate or enchant.
Example
The beauty of the sunset ravished the travelers.
夕日の美しさが旅行者を魅了した。
C1 verb /raɪl/

rile

Meaning
to irritate or annoy someone
Example
His careless comments really riled her.
C2 noun /rɪˈmɒnstrəns/

remonstrance

抗議
Meaning
A forceful protest or objection.
Example
The workers’ remonstrance against unfair treatment was ignored.
労働者たちの不公平な扱いに対する抗議は無視された。
B2 noun /rɪˈlaɪ.əns/

Reliance

依存
Meaning
the state of depending on something or someone for support or help
Example
His reliance on technology is concerning.
技術への依存は懸念すべきことです。
C2 verb /rɛnd/

rend

引き裂く
Meaning
to tear something apart violently or forcefully
Example
The explosion rent the air with a deafening noise.
爆発は耳をつんざくような音で空気を引き裂いた。
B1 adjective /ˈrel.ə.tɪv/

Relative

相対的
Meaning
considered in comparison to something else; not absolute; comparative
Example
The cost of living is relative to your income level.
生活費はあなたの収入レベルに対して相対的です。
C2 adjective /rɪˈprɛsəbl̩/

repressible

抑制可能
Meaning
Capable of being restrained or suppressed.
Example
The movement proved to be hardly repressible.
その運動はほとんど抑制可能であることが証明されました。
B2 noun /ˌreɡ.jʊˈleɪ.ʃənz/

regulations

規制
Meaning
Rules or directives made and maintained by an authority.
Example
Strict regulations ensure fair practices.
厳格な規制は公正な慣行を確保します。
C2 noun /ˈrɛkluːsəri/

reclusory

隠遁場所
Meaning
A place for seclusion or retreat, especially for a recluse or hermit.
Example
The monk spent years in the reclusory away from society.
その僧侶は社会から離れた隠遁場所で数年を過ごしました。
B2 noun /ˈrɒbər/

robber

強盗
Meaning
a person who steals property from others, often using force or threat
Example
The robber was caught after a quick police chase.
素早い警察の追跡の後、強盗は捕まった。
B2 noun /ˈrerəti/

Rarity

珍しい状態; 普通でないもの、または希少なもの
Meaning
the state of being rare; something that is uncommon or scarce
Example
The antique vase was a rarity worth thousands of dollars.
その古代の花瓶は、数千ドルの価値がある珍しいものだった。
C1 noun /ˈroʊ.lɪŋ bɔːrd/

Rolling board

ローリングボード
Meaning
a flat wooden or marble surface used for rolling out dough
Example
She placed the dough on the rolling board.
彼女は生地をローリングボードに置きました。
B2 adjective /rɪˈspɒn.sɪv/

Responsive

反応が早い
Meaning
reacting quickly and positively; readily reacting to suggestions or changes
Example
The website is very responsive and loads quickly on all devices.
そのウェブサイトは非常にレスポンシブで、すべてのデバイスで迅速に読み込まれます。
B2 noun /rɪˈfjuː.zəl/

Refusal

拒否; 拒絶
Meaning
the act of saying no to something or not accepting something
Example
His refusal to cooperate made the project more difficult.
彼の協力拒否はプロジェクトをさらに難しくした。
B2 noun, verb /rɪˈzɔːrt/

resort

リゾート / 最後の手段
Meaning
A place for rest or recreation; to turn to something for help or solution.
Example
They stayed at a beach resort during their vacation.
彼らは休暇中にビーチリゾートに滞在しました。
C1 noun /rɪˈkluːs/

recluse

隠者
Meaning
A person who lives alone and avoids other people; someone who lives a solitary life.
Example
The old man lived as a recluse in the mountains.
その老人は山の中で隠者として暮らしていた。
B2 adjective /rɪˈlaɪ.ənt/

reliant

依存している
Meaning
depending on someone or something for support
Example
The country is too reliant on imported goods.
その国は輸入品に依存しすぎている。
C1 noun /ˈreɪ.biːz/

rabies

狂犬病
Meaning
A viral disease that causes inflammation of the brain in humans and other mammals, usually transmitted through animal bites.
Example
The dog was vaccinated against rabies.
犬は狂犬病のワクチンを接種しました。
B1 noun /ˌrɛp.jʊˈteɪ.ʃən/

reputation

評判, 名声
Meaning
The opinion generally held about someone or something; fame or prestige.
Example
A good reputation is essential for business success.
良い評判はビジネスの成功に不可欠です。
B1 adjective rɪˈlaɪ.ə.bəl

reliable

信頼できる
Meaning
Consistently good in quality or performance; able to be trusted.
Example
Reliable systems ensure efficiency.
信頼できるシステムは効率を確保します。
A2 adjective /rɪˈspɒn.sə.bəl/

Responsible

責任がある; 任務を持っている; 信頼できる
Meaning
accountable; having duties; reliable and trustworthy
Example
Parents are responsible for their children's education and well-being.
親は子供たちの教育と福祉に責任があります。
C2 noun /ˈrɛtɪnjuː/

retinue

従者
Meaning
A group of attendants or followers accompanying an important person.
Example
The king entered the hall followed by his retinue.
王は従者を引き連れてホールに入った。
C2 noun /ˈrɛd.ə.ləns/

redolence

香り
Meaning
a pleasant smell or the quality of suggesting something strongly
Example
The redolence of jasmine filled the evening air.
ジャスミンの香りが夕方の空気を満たした。
C2 noun /rɪˈpoʊst/

riposte

鋭い返答
Meaning
a quick and clever reply to criticism or an insult
Example
Her sharp riposte left everyone in silence.
彼女の鋭い返答は皆を黙らせた。
C1 noun /ˈreɪ.vən/

Raven

ワタリガラス
Meaning
a large, black bird with a thick bill and harsh croaking voice
Example
The raven perched on the old oak tree and cawed loudly.
ワタリガラスが古いオークの木に止まり、大きな声で鳴いた。
B2 verb /rɪˈkɔːl/

recall

思い出す
Meaning
to bring (a memory, fact, or situation) back into one's mind
Example
I can't recall the last time we met.
最後に会った時のことを思い出せません。
C2 verb /ˈrɔɪstər/

roister

大声で祝い
Meaning
to revel noisily; to engage in loud, boisterous celebration
Example
The fans roistered in the streets after the victory.
ファンは勝利後に街で騒いでいました。
C2 verb /ˈrʌmpəl/

rumple

しわにする
Meaning
to make something untidy or wrinkled by creasing or crumpling
Example
She accidentally rumpled her dress while packing.
彼女は荷物を詰める際にドレスをうっかりしわにした。
C1 noun, adjective /ˈrɛvərənd/

reverend

牧師, 尊敬される
Meaning
A title of respect used for members of the clergy; deserving deep respect.
Example
The Reverend gave an inspiring sermon at the church.
レヴァレンドは教会で感動的な説教をしました。
B2 noun /ˈruːmər/

rumor

Meaning
a currently circulating story or report of uncertain or doubtful truth.
Example
There’s a rumor that the company will merge next year.
来年、会社が合併するという噂があります。
C2 noun /rɪˈpruːf/

reproof

叱責, 非難
Meaning
An expression of blame or disapproval.
Example
His careless words drew a sharp reproof from his mother.
彼の不注意な言葉は、母親からの厳しい叱責を引き起こした。
B2 noun rɪˈkruːt.mənt

recruitment

採用
Meaning
The action of finding new people to join an organization or support a cause.
Example
Recruitment strengthens the workforce.
採用は労働力を強化します。
B2 noun /ˈrep.taɪl/

Reptile

爬虫類
Meaning
a cold-blooded animal with scaly skin that lays eggs on land
Example
The lizard is a common reptile found in gardens.
トカゲは庭で見られる一般的な爬虫類です。
C1 noun/verb /ˈræfəl/

raffle

抽選券の販売
Meaning
A means of raising money by selling numbered tickets, one or more of which are drawn at random for a prize; to sell something in such a lottery.
Example
The charity decided to raffle a bicycle to raise funds.
チャリティーは資金調達のために自転車を抽選で販売することに決めました。
C2 noun /ˌrɛprɪˈhɛnʃən/

reprehension

叱責
Meaning
The act of rebuking or criticizing severely.
Example
The teacher’s reprehension of the student’s behavior was justified.
教師の学生の行動に対する叱責は正当であった。
B2 verb /ˌriːəˈreɪndʒ/

rearrange

再配置する
Meaning
to change the order or position of something
Example
She decided to rearrange the furniture in her living room.
彼女はリビングルームの家具を再配置することに決めました。
C1 adjective rɪˈlɛntləs

relentless

容赦ない
Meaning
Oppressively constant; incessant; showing no abatement of severity, intensity, strength, or pace.
Example
The freedom fighters' relentless struggle led to victory.
自由戦士たちの容赦ない戦いは勝利へと導いた。
B2 noun /ˌriː.əˈʃʊr.əns/

Reassurance

安心
Meaning
comfort or confidence given to someone to remove their fears or doubts
Example
She needed reassurance that everything would be okay.
彼女はすべてがうまくいくことを確認するために安心が必要でした。
B2 noun /rɪˈmaɪndər/

reminder

リマインダー
Meaning
something that helps you remember a fact, event, or action that you need to do or recall
Example
He set a reminder to call his mother on her birthday.
彼は母親の誕生日に電話するためにリマインダーを設定しました。
B1 noun ˌrekəɡˈnɪʃn

recognition

認識
Meaning
Acknowledgment of the existence, validity, or legality of something; appreciation or acclaim for an achievement, service, or ability.
Example
He earned recognition after years of struggle.
彼は長年の努力の後、認識を得ました。
B2 noun /rɪˌlaɪəˈbɪləti/

reliability

信頼性
Meaning
the quality of being trustworthy or performing consistently well
Example
Customers value the reliability of our service.
お客様は私たちのサービスの信頼性を重視しています。
C1 verb /rɪˈsiːd/

recede

後退する
Meaning
To move back or further away from a previous position.
Example
The floodwaters began to recede after the heavy rain stopped.
激しい雨が止んだ後、洪水は後退し始めました。
C1 noun /rɪˈsɜː.dʒəns/

resurgence

再生
Meaning
An increase or revival after a period of little activity, popularity, or occurrence.
Example
The city saw a resurgence in tourism after the pandemic.
都市はパンデミック後、観光業の再生を見ました。
C2 adjective /rəˈkoʊkoʊ/

rococo

ロココ
Meaning
characterized by ornate detail and elaborate decoration, especially in art, architecture, and design
Example
The palace was decorated in a lavish rococo style.
宮殿は豪華なロココ様式で装飾されていました。
C1 verb /rɪˈvɜːrbəreɪt/

reverberate

反響する
Meaning
To echo repeatedly or have continuing effects.
Example
The sound of the explosion reverberated through the valley.
爆発音は谷を通り過ぎて反響しました。
B2 noun /rɪˈhɜːr.səl/

Rehearsal

リハーサル; 公演の練習
Meaning
a practice performance of a play, concert, or other work for later public performance
Example
The final rehearsal before opening night went perfectly.
開幕前の最後のリハーサルは完璧でした。
C1 verb /riːˈpeɪ.tri.eɪt/

repatriate

帰還させる
Meaning
To return someone to their own country, often after war or imprisonment.
Example
The government worked to repatriate the refugees safely.
政府は難民を安全に帰国させるために尽力しました。
B2 noun /roʊˈteɪʃən/

Rotation

回転; 回転運動; 自転
Meaning
the action of rotating around an axis or center; a single turn
Example
The Earth's rotation takes 24 hours to complete.
地球の回転は24時間かかります。
B1 adjective /ˌriːəˈlɪstɪk/

realistic

現実的
Meaning
having or showing a sensible and practical idea of what can be achieved or expected
Example
She gave a realistic estimate of the project's cost.
彼女はプロジェクトのコストの現実的な見積もりを出した。
B2 noun /rɪˈdʒɛkʃən/

rejection

拒絶
Meaning
the action of refusing or dismissing something or someone
Example
Her rejection of the offer surprised everyone.
彼女の提案の拒絶は皆を驚かせた。
C1 noun /ˌriː.əˈdʒʌst.mənt/

readjustment

Meaning
The act of changing or correcting something again to make it suitable or balanced.
Example
After moving to a new city, he went through a period of readjustment.
C1 noun /rɪˈspɒnsɪvnəs/

responsiveness

反応性
Meaning
The quality of reacting quickly and positively
Example
The manager appreciated her responsiveness to customer feedback.
マネージャーは彼女の顧客からのフィードバックに対する反応性を評価しました。
B2 noun /reɪˈʒiːm/

regime

政権
Meaning
a system or form of government, often authoritarian
Example
The military regime controlled the country for decades.
軍事政権は数十年間国を支配していました。
B2 noun/verb /rɪˈmɑːrk/

remark

発言
Meaning
something that is said; a comment
Example
She made a remark about the weather.
彼女は天気について発言した。
B2 noun /ˌrɪəlɪˈzeɪʃən/

realization

実現
Meaning
the act of becoming fully aware of something as a fact
Example
Her realization of the problem helped solve the issue.
彼女の問題の認識が問題解決に役立った。
C1 adjective /ˈroʊ.ɡɪʃ/

Roguish

いたずらな; 狡猾な
Meaning
mischievous; playfully dishonest
Example
His roguish smile suggested he was up to some mischief.
彼のいたずらな笑顔は、彼が何かいたずらを仕掛けていることを示唆していました。
C1 noun /rɑk sɔlt/

Rock Salt

岩塩
Meaning
natural salt crystals formed from evaporated ancient seas; unrefined salt
Example
Rock salt is considered healthier than table salt.
岩塩はテーブルソルトよりも健康的だと考えられています。
B1 adverb /ˈrel.ə.tɪv.li/

Relatively

相対的に
Meaning
in comparison to something else; quite; fairly
Example
The weather is relatively warm today.
今日の天気は相対的に暖かい。
C1 noun /rɪˈdʒɪdəti/

Rigidity

剛性
Meaning
inability to bend or be forced out of shape; unwillingness to change or compromise
Example
The rigidity of the old system prevented any innovation.
古いシステムの剛性は、どんな革新も妨げました。
C2 noun /ˈræp.aɪn/

rapine

略奪
Meaning
the violent seizure of someone's property
Example
The war was marked by rapine and destruction.
戦争は略奪と破壊で特徴づけられていた。
C2 noun /rɪˈsɪdɪˌvɪzəm/

recidivism

Meaning
The tendency of a convicted criminal to reoffend or relapse into criminal behavior.
Example
The government introduced new programs to reduce recidivism among former inmates.
B2 adjective /ˈrek.ləs/

Reckless

無謀な; 無鉄砲な; 危険な;
Meaning
acting without thinking about consequences; careless; dangerous;
Example
His reckless driving caused a serious accident.
彼の無謀な運転は深刻な事故を引き起こしました。
C2 noun/verb /ˈrɛkəmˌpɛns/

recompense

賠償
Meaning
to compensate someone for loss or harm suffered; compensation given for damage or injury
Example
The company offered financial recompense to the injured worker.
その会社は負傷した労働者に対して金銭的な賠償を提供しました。
B2 noun /rɪˈbel.jən/

Rebellion

反乱
Meaning
an act of armed resistance to an established government or leader
Example
The rebellion against the king lasted for three years.
王に対する反乱は3年間続いた。
C1 verb /ˈrætɪfaɪ/

ratify

批准する
Meaning
to approve or confirm something officially, usually by law or formal consent
Example
The government ratified the trade agreement.
政府は貿易協定を批准しました。
C2 adjective /ˈruːbɪkənd/

rubicund

健康的な赤みを帯びた顔
Meaning
Having a healthy reddish complexion.
Example
The old man’s rubicund face showed he was in good health.
その老人の赤みを帯びた顔は、彼が健康であることを示していた。
B2 verb /ˌriː.kənˈstrʌkt/

reconstruct

再建する
Meaning
to build or form something again after it has been damaged or destroyed
Example
The city was reconstructed after the earthquake.
その都市は地震後に再建されました。
B1 adjective /roʊˈmæn.tɪk/

Romantic

ロマンチック
Meaning
relating to love; idealistic; dreamy
Example
They enjoyed a romantic dinner by candlelight.
彼らはろうそくの光でロマンチックなディナーを楽しんでいました。
B2 noun /ˈreɪʃoʊ/

ratio

比率
Meaning
a relationship between two numbers showing how many times the first number contains the second
Example
The ratio of boys to girls in the class is 2:1.
クラスでの男の子と女の子の比率は2:1です。
C1 adjective /ˈriːɡəl/

regal

王室の
Meaning
Resembling or fit for a king; majestic or royal.
Example
The queen entered the hall with a regal presence.
女王は王室のような存在感でホールに入った。
B2 verb /ræm/

ram

Meaning
to strike or push something with great force
Example
The truck rammed into the wall.
A2 adverb /ˈrɛɡjələrli/

regularly

定期的に
Meaning
at regular intervals; in a regular manner
Example
She exercises regularly to stay healthy.
彼女は健康を保つために定期的に運動します。