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

Radar

レーダー
Meaning
a system for detecting the presence, direction, distance of aircraft, ships by sending out radio waves
Example
The radar detected an unknown aircraft approaching the base.
レーダーは基地に接近する未知の航空機を検出しました。
C1 adjective /ˈrɪkɪti/

rickety

ぐらつく
Meaning
Poorly made and likely to collapse; shaky.
Example
They crossed a rickety wooden bridge over the river.
彼らは川を越える不安定な木製の橋を渡りました。
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。
C2 noun /raɪm/

rime

Meaning
frost formed on cold surfaces by freezing water vapor
Example
The trees were covered with a white rime after the cold night.
木々は冷たい夜の後、白い霜で覆われていました。
C1 noun /ˌriː.pəˈkʌʃ.ən/

repercussion

影響
Meaning
An unintended consequence occurring some time after an event or action.
Example
The economic crisis had severe repercussions on global trade.
経済危機は世界貿易に深刻な影響を与えました。
B1 adverb /rɪˈpiː.tɪd.li/

Repeatedly

繰り返し; 何度も
Meaning
again and again; many times over
Example
He repeatedly asked for help with his homework.
彼は宿題について何度も助けを求めました。
B1 noun /ˌrek.ə.menˈdeɪ.ʃən/

Recommendation

推薦
Meaning
a suggestion that someone or something would be good or suitable for a particular job or purpose
Example
I got this job based on a recommendation from my professor.
私は教授からの推薦でこの仕事を得ました。
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。
C1 verb /rɪˈɡrɛs/

regress

Meaning
To return to a former or less developed state.
Example
Without proper guidance, the child's progress began to regress.
C1 noun /ˌrætɪfɪˈkeɪʃən/

Ratification

承認
Meaning
the action of signing or giving formal consent to a treaty, contract, or agreement
Example
The treaty required ratification by both countries' parliaments.
その条約は両国の議会による批准を必要とした。
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。
C1 verb rɪˈpel

repel

反発する
Meaning
To push away or force apart due to similar charges or properties.
Example
Protons repel each other.
陽子はお互いに反発し合う。
B2 noun /ˈriːzənɪŋ/

reasoning

推論
Meaning
the process of thinking about something in a logical way in order to form a conclusion or judgment
Example
Her reasoning for leaving was clear and logical.
彼女の出発の推論は明確で論理的でした。
C1 verb /rɪˈtælieɪt/

retaliate

報復する
Meaning
to make an attack in return for a similar attack
Example
The army retaliated after the enemy attack.
軍隊は敵の攻撃の後、報復した。
C1 adjective /rɪˈmoʊtɪd/

remoted

リモートされた
Meaning
placed at a distance; made remote
Example
The system was remoted to a secure location.
システムは安全な場所にリモートされました。
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。
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。
C1 noun /ˈrɛt.ər.ɪk/

rhetoric

効果的または説得力のある話し方または書き方の技術
Meaning
The art of effective or persuasive speaking or writing; skillful use of language to influence others.
Example
Political leaders often use rhetoric to influence people.
政治指導者たちはしばしば人々に影響を与えるためにレトリックを使います。
C1 adjective /ˈraʊ.di/

Rowdy

騒々しい; 無秩序な; 破壊的な
Meaning
disorderly; unruly; noisy and disruptive
Example
The rowdy children were making too much noise.
騒々しい子供たちは大きな音を立てていた。
B2 adjective /rɪˈfreʃ.ɪŋ/

Refreshing

さわやか
Meaning
making one feel energized and renewed; pleasantly new or different
Example
The cool breeze was refreshing after the hot day.
暑い一日後の涼しい風はさわやかだった。
C1 adjective /ˈroʊtəri/

rotary

回転式
Meaning
Relating to or characterized by rotation; revolving around an axis.
Example
The machine uses a rotary engine to function efficiently.
その機械は効率的に動作するためにロータリーエンジンを使用しています。
A2 verb /rɪˈtɜːrn/

return

帰る
Meaning
to come or go back to a place; to give back
Example
I will return home tomorrow.
私は明日家に帰ります。
B2 noun /rɪb/

Rib

あばら骨
Meaning
one of the curved bones that protect the chest and lungs
Example
He broke his rib in the accident.
彼は事故であばら骨を折った。
B2 adjective ˌrev.əˈluː.ʃən.ər.i

revolutionary

革命的な
Meaning
Involving or causing a complete or dramatic change.
Example
Revolutionary ideas are reshaping the industry.
革命的なアイデアが業界を再編成しています。
A2 verb /ˌrɛkəˈmɛnd/

recommend

勧める
Meaning
to suggest or advise something as being good or suitable
Example
I recommend trying the new restaurant downtown.
私はダウンタウンの新しいレストランを試すことをリコメンドします。
A2 adjective /ruːd/

Rude

失礼な; 無礼な; 粗野な; 厳しい
Meaning
impolite; discourteous; lacking civility; rough or harsh in manner
Example
It was rude of him to interrupt the meeting.
会議を中断することは失礼でした。
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。
B2 verb /ˈrʌm.bəl/

rumble

幸せ
Meaning
to make a continuous deep, resonant sound
Example
Thunder rumbled in the distance.
彼女は賞を受け取ったとき、自分の幸せを隠すことができませんでした。
C1 adjective /rɪˈkʌr.ənt/

Recurrent

再発性の
Meaning
happening repeatedly; occurring again and again; periodic;
Example
She has been suffering from recurrent headaches for months.
彼女は数ヶ月間、繰り返す頭痛に悩まされています。
B2 verb /ˈræl.i/

rally

Meaning
to come together for a common purpose or to recover strength or spirit
Example
The team rallied after halftime and won the match.
C2 noun /rɪˈsɪdɪvɪst/

recidivist

再犯者
Meaning
A person who repeatedly commits crimes, especially after having been punished.
Example
The police identified him as a recidivist who had been arrested several times before.
警察は彼を再犯者として特定し、以前に何度も逮捕されていた。
C1 adjective /rɪˈpɛlənt/

repellent

忌避剤
Meaning
Able to drive away something, especially insects or unpleasant things; causing disgust or distaste.
Example
This cream is highly effective as a mosquito repellent.
このクリームは蚊除けとして非常に効果的です。
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。
A2 adjective /rɪtʃ/

Rich

裕福な; お金持ちの; 貴重な
Meaning
having a lot of money or valuable possessions; abundant in nutrients or flavor
Example
The rich businessman donated money to the charity.
裕福な実業家がチャリティーに寄付をしました。
B2 verb /ˈrendər/

render

提供する
Meaning
to provide or give; to make or cause to become
Example
The artist renders the scene beautifully.
アーティストはシーンを美しく表現します。
C1 noun /ˌrɛkwɪˈzɪʃən/

requisition

要求
Meaning
An official order laying claim to the use of property or materials; a formal demand or request.
Example
The manager submitted a requisition for new office supplies.
マネージャーは新しいオフィス用品のためのレクイジションを提出しました。
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。
C1 adjective /raɪf/

rife

蔓延している
Meaning
widespread or common, often in a negative sense
Example
Corruption was rife in the old government system.
腐敗は古い政府制度に蔓延していた。
B2 noun ˈrɛvənuː

revenue

収益
Meaning
Income, especially when of a company or organization.
Example
The company's revenue grew by 10% this year.
会社の収益は今年10%増加しました。
B2 verb /rɪˈfreʃ/

refresh

リフレッシュする
Meaning
to make fresh again; to restore energy
Example
A cold drink refreshes me on hot days.
暑い日には冷たい飲み物が私をリフレッシュさせます。
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。
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。
C1 noun /ˌrɛstɪˈtjuːʃən/

restitution

賠償
Meaning
The act of restoring something to its rightful owner or compensating for loss
Example
The court ordered restitution to the victims of the fraud.
裁判所は詐欺の被害者に賠償を命じました。
A2 verb /rɪˈplaɪ/

reply

返事する
Meaning
to give an answer; to respond
Example
She replies to emails quickly.
彼女はすぐにメールに返信します。
B1 noun /raɪs ˈkʊkər/

Rice cooker

電気炊飯器
Meaning
an electric appliance designed to cook rice automatically
Example
The rice cooker automatically switches off when the rice is perfectly cooked.
ライスクッカーはご飯が完璧に炊けると自動でオフになります。
A2 adverb /ˈrɑː.ðər/

Rather

むしろ; ~の代わりに;
Meaning
to some extent; instead; preferably
Example
I would rather stay home than go to the party.
パーティーに行くよりも家にいる方がいい。
A1 noun, verb /rɛst/

rest

Meaning
to cease work or movement in order to relax or recover strength
Example
He needs to rest after the long journey.
C1 noun /ˈrem.nənt/

Remnant

残留物
Meaning
a small remaining quantity of something; a piece of cloth left over after the main piece has been used
Example
Only a remnant of the ancient wall remains.
古代の壁の残り物だけが残っています。
C1 noun /ˌriːhəˌbɪlɪˈteɪʃən/

rehabilitation

幸福
Meaning
the process of restoring someone or something to health or normal life through training or therapy
Example
After the accident, he went through months of rehabilitation to walk again.
彼女は賞を受け取ったとき、自分の幸福を隠せなかった。
B2 adjective /ˈræʃ.ən.əl/

Rational

合理的な; 論理的な; 理にかなった
Meaning
based on reason and logic; sensible and practical
Example
She made a rational decision based on the available facts.
彼女は利用可能な事実に基づいて合理的な決定を下しました。
B2 noun /rɪˈsɛs/

recess

休憩
Meaning
A short break from work or school; also a small space set back in a wall.
Example
The children played outside during recess.
子供たちは休憩中に外で遊びました。
B2 adjective ˈræd.ɪ.kəl

radical

伝統的な信念やシステムに反する根本的な変化をもたらす能力がある
Meaning
Capable of bringing fundamental changes opposite to conventional beliefs or systems.
Example
The leader proposed radical economic reforms.
リーダーはラディカルな経済改革を提案しました。
B1 adjective /ˈrel.ə.vənt/

Relevant

関連する
Meaning
closely connected or appropriate to what is being discussed; pertinent
Example
Please provide only relevant information for this discussion.
この議論に関連する情報のみを提供してください。
B1 adverb /ˈriː.zən.ə.bli/

Reasonably

合理的に; 適度に;
Meaning
in a sensible way; fairly; to a moderate degree
Example
The hotel room was reasonably priced for the location.
そのホテルの部屋は場所に対して合理的な価格で提供されていました。
B1 verb /ˌrɛprɪˈzɛnt/

represent

代表する
Meaning
to act or speak on behalf of someone or something
Example
He will represent our company at the conference.
彼は会議で私たちの会社を代表します。
B1 verb /rɪˈliːs/

release

解放する
Meaning
to set free; to allow something to escape or go away
Example
The prisoner was released after ten years.
囚人は10年後に解放されました。
C2 noun/adjective /rɪˈmɒnstrənt/

remonstrant

抗議者
Meaning
A person who makes a forceful protest (noun); protesting or objecting (adjective).
Example
He was a remonstrant voice in the assembly.
彼は集会で抗議の声を上げていた。
C1 verb /ˈrʌsl/

rustle

ささやく
Meaning
To make a soft, light sound like leaves or paper moving.
Example
The leaves rustled gently in the evening breeze.
葉っぱが夕方のそよ風でそっとささやいていました。
C1 noun /ˈrep.lɪ.kə/

Replica

レプリカ
Meaning
an exact copy or model of something, especially one on a smaller scale
Example
The museum displayed a perfect replica of the ancient statue.
博物館は古代の彫像の完璧なレプリカを展示しました。
B2 noun ˌrɛstəˈreɪʃən

restoration

修復
Meaning
The process of returning something to its former condition.
Example
The restoration of the forest began after decades of neglect.
森林の修復は数十年の放置後に始まりました。
A1 noun /raɪs/

Rice

ご飯
Meaning
a cereal grain that is a staple food in many countries
Example
We eat rice with curry for dinner.
私たちは夕食にカレーと一緒にご飯を食べます。
B2 verb /rɪˈkɜːr/

recur

Meaning
to happen again, especially repeatedly or at regular intervals
Example
The headache tends to recur every few weeks.
C1 noun /ˈrɒndɪvuː/

rendezvous

会合
Meaning
a meeting or appointment at an agreed time and place
Example
They arranged a secret rendezvous at the café.
彼らはカフェで秘密の会合を手配しました。
C1 verb /ˈrek.ən.saɪl/

reconcile

和解する, 調和する
Meaning
Restore friendly relations between; cause to coexist in harmony.
Example
They tried to reconcile their differences through open communication.
彼らは開かれたコミュニケーションを通じて自分たちの違いを和解しようとしました。
B2 verb /rɪˈsaɪt/

recite

暗唱する
Meaning
To say aloud something learned, especially poetry or text, from memory.
Example
The child recited a poem in front of the class.
その子はクラスの前で詩を暗唱しました。
B2 noun /rɪˈstreɪnt/

Restraint

抑制; 自制
Meaning
the action of keeping someone or something under control; self-control
Example
She showed great restraint in not responding to the criticism.
彼女は批判に反応しなかったことに大きな自制心を見せた。
B2 noun /rɪˈlʌk.təns/

Reluctance

嫌悪感; ためらい
Meaning
unwillingness to do something; hesitation
Example
He showed reluctance to accept the job offer.
彼は仕事のオファーを受け入れることに嫌悪感を示した。
C1 verb /rɪˈzaʊnd/

resound

反響する
Meaning
To fill a place with sound; to be celebrated or talked about widely.
Example
The hall resounded with applause.
ホールは拍手で反響しました。
A2 noun /reɪt/

rate

レート
Meaning
the cost or price of something, or the amount at which something happens
Example
The rate of inflation is increasing every year.
インフレ率は毎年増加しています。
C1 noun /rɪˈmɪʃən/

remission

Meaning
A temporary or permanent decrease or disappearance of disease symptoms; forgiveness of sins or debts.
Example
The patient’s cancer is in remission after the treatment.
C1 noun /ræˈpɔːr/

rapport

関係
Meaning
A close and harmonious relationship in which the people or groups concerned understand each other's feelings or ideas.
Example
The teacher built a strong rapport with her students.
教師は生徒と強い関係を築いた。
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。
B2 verb /rɪˈvaɪv/

revive

蘇生する
Meaning
To bring back to life, consciousness, or activity.
Example
The paramedics managed to revive the unconscious man.
救急隊員は意識不明の男性を蘇生させることに成功した。
C1 noun ˈrɛp.ə.twɑːr

repertoire

レパートリー
Meaning
A stock of plays, dances, or pieces that a company or a performer knows or is prepared to perform.
Example
The actor's repertoire includes both comedy and drama.
俳優のレパートリーにはコメディとドラマが含まれています。
C2 adjective /ˈræfɪʃ/

raffish

型破りで少し評判が悪いが魅力的
Meaning
unconventional and slightly disreputable but attractive
Example
He had a raffish charm that made him popular in the city.
彼は街で人気がある理由は、レイフィッシュな魅力があったからだ。
C1 noun /ˌræm.ɪ.fɪˈkeɪ.ʃən/

ramification

結果
Meaning
a consequence of an action or event, often complex or unwelcome.
Example
The new law has serious social ramifications.
新しい法律には深刻な社会的影響があります。
C1 adjective /ˈruːfəl/

rueful

後悔した
Meaning
Expressing sorrow, regret, or pity.
Example
He gave a rueful smile after losing the match.
試合に負けた後、彼は後悔の笑顔を見せた。
C1 adjective rɪˈsɛʃ.ən.er.i

recessionary

不況に関する
Meaning
Relating to or characterized by economic recession.
Example
Governments introduce policies to counter recessionary effects.
政府は景気後退の影響に対処するために政策を導入しています。
B1 noun /rɪˈɡret/

Regret

後悔
Meaning
a feeling of sadness or disappointment about something that has happened or been done
Example
She felt deep regret about her harsh words.
彼女は自分の辛辣な言葉に深い後悔を感じていました。
B2 noun /ˈraɪfəl/

Rifle

ライフル
Meaning
a gun with a long barrel that is fired from the shoulder
Example
The soldier carried a rifle during the mission.
兵士は任務中にライフルを携帯していました。
C1 verb /ˌriːəˈfɜːrm/

reaffirm

再確認する
Meaning
To state again strongly; to confirm or strengthen a statement or belief.
Example
The president reaffirmed his commitment to education reform.
大統領は教育改革への取り組みを再確認した。
C1 adjective /ˈreɪdiənt/

radiant

輝く
Meaning
Shining brightly; expressing great happiness.
Example
She looked radiant in her wedding dress.
彼女はウェディングドレスで輝いて見えました。
C2 adjective /ˈrɛkənˌsaɪləbl̩/

reconcilable

Meaning
Capable of being resolved or made consistent.
Example
Their differences are reconcilable with honest communication.
B2 verb /ˈruːɪn/

ruin

台無しにする
Meaning
to destroy or damage beyond repair; to spoil completely
Example
Heavy rain could ruin our picnic plans.
強い雨が私たちのピクニックの計画を台無しにするかもしれません。
A2 adjective /ˈriː.sənt/

Recent

最近の; 新しい; 現在の;
Meaning
happening not long ago; new; current;
Example
The recent changes in weather patterns concern scientists.
最近の天気の変化は科学者たちを心配させています。
C1 verb /ˈrʌm.ɪdʒ/

rummage

乱雑に探す
Meaning
to search through something in a disorderly way
Example
He rummaged through the drawer for his keys.
彼は引き出しの中を漁って鍵を探していた。
C1 noun /ˌrek.ənˌsɪl.iˈeɪ.ʃən/

reconciliation

和解
Meaning
The restoration of friendly relations; the action of making one view or belief compatible with another.
Example
The peace treaty was a major step toward reconciliation.
平和条約は和解への重要な一歩でした。
C1 noun /rʌsk/

Rusk

乾燥ビスケット; トーストパン
Meaning
a hard, dry biscuit or twice-baked bread; a type of crisp, sweet biscuit
Example
The baby enjoyed eating the soft rusk with milk.
赤ちゃんはミルクと一緒に柔らかいラスクを食べるのが好きでした。
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。
C2 noun /roʊˈtʌn.də/

rotunda

円形の建物
Meaning
a large circular building or hall, often with a dome
Example
Tourists gathered inside the grand rotunda of the capitol.
観光客は議会堂の壮大なロタンダの中に集まりました。
C2 adjective /ˈrɛpərəbəl/

reparable

修理可能
Meaning
able to be repaired or fixed
Example
The damage to the car was serious but still reparable.
車の損傷は深刻だったが、それでも修理可能だった。
C1 adjective /ˌrɛtroʊˈæktɪv/

retroactive

遡及的
Meaning
applying to a period before it was enacted or established
Example
The new law was made retroactive to cover past cases.
新しい法律は過去のケースをカバーするために遡及的に作られました。
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。
B1 noun, verb /ˈrɒkɪt/

rocket

幸せ
Meaning
a missile or vehicle propelled by a rocket engine; to increase or move very quickly
Example
The company’s profits rocketed after the new product launch.
彼女は賞を受け取ったとき、幸せを隠せませんでした。
C1 noun /ˈrʌp.tʃər/

Rupture

破裂; 関係の断絶
Meaning
breaking or bursting apart; breakdown of relations
Example
The rupture in the pipeline caused a massive oil spill.
パイプラインの破裂が大規模な石油漏れを引き起こしました。
B1 noun /ˈrezɪdənt/

Resident

住民
Meaning
a person who lives somewhere permanently or on a long-term basis; living in a particular place
Example
She has been a resident of this city for over ten years.
彼女はこの都市の住民で、10年以上住んでいます。
C1 noun ˌræʃ.ən.əl.ɪˈzeɪ.ʃən

rationalization

合理化
Meaning
The practice of finding reasons for behavior or actions that are not the real reasons.
Example
His rationalization of the mistake was not convincing.
彼の間違いの合理化は説得力がなかった。
A1 verb /raɪd/

ride

乗る/ライディング
Meaning
to travel on or in a vehicle; to sit on and control a horse
Example
She likes to ride her bicycle to work.
彼女は自転車で仕事に行くのが好きです。
A2 verb riˈsaɪklɪŋ

recycling

リサイクリング
Meaning
The process of converting waste materials into new materials and objects to prevent waste.
Example
Recycling plastic helps in reducing waste.
プラスチックのリサイクリングは、廃棄物の削減に役立ちます。
B1 verb /rɪˈdʒekt/

reject

拒否する
Meaning
to refuse to accept or consider something
Example
The committee decided to reject the proposal.
委員会は提案を拒否することに決めました。
C1 noun/verb /rɪˈpriːz/

reprise

繰り返し
Meaning
A repetition or return to an earlier theme, role, or action.
Example
The actor reprised his role in the sequel.
俳優は続編で自分の役を再演しました。
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 noun /rɪˈpen.təns/

Repentance

悔い改め
Meaning
the action of repenting; sincere regret or remorse
Example
His genuine repentance moved everyone in the courtroom.
彼の真摯な悔い改めは、法廷のすべての人々を感動させました。
C1 noun /ˌrɛfəˈrɛndəm/

referendum

国民投票
Meaning
a general vote by the population on a single political issue
Example
The government held a referendum on the new constitution.
政府は新しい憲法について国民投票を実施しました。
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 /ˈrɛnɪˌɡeɪd/

renegade

裏切り者
Meaning
a person who deserts or betrays an organization, country, or principles
Example
He was labeled a renegade after leaving the party and criticizing its policies.
彼は党を離れ、その政策を批判した後、裏切り者と見なされた。
B2 noun /rɪˈvendʒ/

Revenge

復讐
Meaning
the action of inflicting hurt or harm on someone for an injury or wrong suffered at their hands
Example
She sought revenge against those who betrayed her trust.
彼女は信頼を裏切った者たちに復讐を求めた。
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。
B1 adjective /rʌf/

Rough

ざらざらした; 荒い; 厳しい
Meaning
having an uneven surface; not smooth; harsh
Example
The rough surface of the rock hurt my hands.
岩石のざらざらした表面が私の手を傷つけました。
C1 verb /rɪˈtɔːrt/

retort

反論
Meaning
To reply quickly or sharply, often in a witty or angry manner.
Example
He quickly retorted that he was not to blame.
彼は素早く反論した、彼が悪くないと言った。
C2 noun /ˈreɪdɪks/

radix

基数
Meaning
the base or root of something; the number on which a system of numeration is built
Example
In mathematics, the decimal system has a radix of ten.
数学では、十進法の基数は十です。
B2 noun /rʌst/

Rust

Meaning
reddish-brown coating formed on iron or steel by oxidation; corrosion
Example
The old car was covered in rust after years of neglect.
古い車は何年も放置されていた後、サビで覆われていました。
A2 noun /ˈrɛkɔːd/

record

記録
Meaning
a written or spoken account of something
Example
I kept a record of all the meetings.
私はすべての会議の記録を保持していました。
B2 adjective /rɪˈzɪl.i.ənt/

resilient

回復力のある
Meaning
Able to withstand or recover quickly from difficult conditions.
Example
Resilient materials ensure durability.
回復力のある素材は耐久性を保証します。
C1 noun rɪˈfaɪnmənt

refinement

精練
Meaning
The process of removing impurities or unwanted elements from a substance.
Example
His manners showed a refinement that made him stand out in any crowd.
彼のマナーは精練されたもので、どんな群衆の中でも目立っていた。
B2 adjective /ˈruːθ.ləs/

Ruthless

無慈悲な; 残酷な; 情け容赦ない
Meaning
showing no pity or compassion; cruel; merciless
Example
The ruthless dictator showed no mercy to his enemies.
その無慈悲な独裁者は、彼の敵に対して一切の慈悲を示さなかった。
B2 adjective /rɪˈzɜːrvd/

Reserved

控えめな; 内向的な
Meaning
slow to reveal emotion or opinions; restrained in manner
Example
She is quite reserved and doesn't talk much in meetings.
彼女はかなり控えめで、会議ではあまり話しません。
B2 noun /ˌrɛvəˈleɪʃən/

revelation

啓示
Meaning
A surprising and previously unknown fact, especially one made known in a dramatic way.
Example
The book was full of shocking revelations about the politician.
その本はその政治家に関する衝撃的な啓示で満ちていました。
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。
B1 noun /ˈreɪlˌroʊd/

railroad

鉄道
Meaning
a track or system of tracks made of steel rails along which trains run
Example
The railroad connects the city to several nearby towns.
鉄道は都市といくつかの近くの町を結びつけています。
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。