rover
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C1 noun ˈrəʊvə

rover

ローバー
Meaning
A vehicle for driving over rough terrain, especially one driven by remote control over extraterrestrial terrain.
Example
The rover landed on Mars to begin its exploration.
ローバーは火星に着陸し、探査を開始しました。
B2 adjective /rɪˈsɔːrsfəl/

resourceful

Meaning
Having the ability to find quick and clever ways to overcome difficulties.
Example
She is very resourceful when it comes to solving unexpected problems.
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 verb /ˌriːˈkæl.ɪ.breɪt/

recalibrate

再調整する, 調整し直す
Meaning
To calibrate again or differently; to adjust or correct something based on new information or changed circumstances.
Example
The company had to recalibrate its strategies to adapt to the market.
会社は市場に適応するために戦略を再調整する必要があった。
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。
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。
B1 noun /ˌrɛdʒɪˈstreɪʃən/

registration

登録
Meaning
the action or process of enrolling or signing up for something
Example
The registration for the event will close tomorrow.
イベントの登録は明日締め切りです。
C1 verb /rɪˈnaʊns/

renounce

放棄する
Meaning
to formally declare rejection of something, such as a claim, belief, or way of life
Example
She renounced her citizenship to move abroad permanently.
彼女は永住権を得るために市民権を放棄しました。
C1 noun /ˌrɛfjʊˈteɪʃən/

refutation

反証
Meaning
The act of proving a statement or argument to be false or incorrect.
Example
Her essay was a strong refutation of the opposing theory.
彼女のエッセイは反対の理論に対する強い反証でした。
C1 verb /riːˈkæptʃər/

recapture

再び奪回する
Meaning
To take back or regain possession of something.
Example
The army managed to recapture the lost territory.
軍隊は失われた領土を再び奪回することに成功しました。
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 adverb /rɪˈɡɑrdləs/

regardless

関係なく
Meaning
without paying attention to the current situation or condition
Example
She will go to the party regardless of the weather.
彼女は天気に関係なくパーティーに行きます。
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。
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 /rɛnˈdɪʃən/

rendition

演奏
Meaning
a performance or interpretation of a piece of art, music, or text
Example
The singer gave a moving rendition of the classic song.
歌手はクラシックな歌の感動的な演奏を行いました。
C1 verb /rɪˈfjuːt/

refute

反論する
Meaning
To prove a statement, argument, or theory to be false or invalid.
Example
The lawyer refuted the witness's testimony with solid evidence.
弁護士は証人の証言を確かな証拠で反論しました。
C1 verb /ˌriː.ɪˈstæblɪʃ/

reestablish

再建する
Meaning
to set up or restore something again after it has been disrupted
Example
The government worked hard to reestablish peace in the region.
政府は地域の平和を再建するために懸命に働きました。
B2 noun, verb /ˈrætəl/

rattle

ガタガタ鳴る；ガラガラ
Meaning
to make a rapid series of short, sharp sounds; a device or object that makes such a sound
Example
The loose window began to rattle in the strong wind.
強い風で緩んだ窓がガタガタ鳴り始めた。
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。
A2 adjective /ˈreɡ.jə.lər/

Regular

定期的な
Meaning
happening at fixed intervals; consistent; normal; frequent
Example
She goes for regular exercise every morning at 6 AM.
彼女は毎朝6時に定期的な運動をします。
C1 noun rɪˌdʒɛnəˈreɪʃən

regeneration

再生
Meaning
Renewal, growth and development of cells, tissues or energy
Example
Proper rest allows muscle regeneration after exercise.
適切な休息は、運動後の筋肉の再生を促進します。
B2 noun /rɪˈzembləns/

Resemblance

類似
Meaning
the state of being alike or similar; similarity in appearance or character
Example
There's a strong resemblance between the two sisters.
二人の姉妹の間には強い類似があります。
C2 verb /rɪˈkjʊə/

recure

再治療する
Meaning
to cure again; to remedy a second time
Example
The doctor had to recure the wound after it reopened.
医者は傷が再び開いた後、傷を再治療する必要がありました。
C1 adjective /ræpt/

Rapt

夢中な
Meaning
completely fascinated or absorbed by what one is seeing or hearing
Example
The children listened with rapt attention to the storyteller.
子供たちは物語の語り手に夢中で耳を傾けました。
C2 verb /ˌriːkruːˈdɛs/

recrudesce

再発
Meaning
to break out or appear again after a period of dormancy or decline
Example
After months of calm, violence recrudesced in the region.
数ヶ月の静けさの後、暴力が再発しました地域で。
C2 adjective /rɪˈdaʊ.tə.bəl/

redoubtable

恐ろしい/尊敬すべき
Meaning
formidable, especially as an opponent; inspiring fear or respect
Example
She was a redoubtable leader who commanded respect from all.
彼女は全員から尊敬を集める恐ろしいリーダーだった。
A2 noun /ˈreɪl.weɪ/

Railway

鉄道
Meaning
a track made of steel rails along which trains run; a system of tracks with trains, stations, and other facilities
Example
The railway connects major cities across the country.
鉄道は国内の主要な都市を結んでいます。
C1 adjective /rɪˈsɛptɪv/

receptive

受容的
Meaning
Willing to listen to or accept new ideas, suggestions, or experiences.
Example
She was receptive to feedback from her colleagues.
彼女は同僚からのフィードバックを受け入れる姿勢を持っていました。
B1 noun /rɪˈsɜːtʃə(r)/

researcher

研究者
Meaning
a person who conducts research
Example
The researcher published her findings in a scientific journal.
研究者は科学的なジャーナルに彼女の研究結果を発表しました。
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 /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 verb /rɒmp/

romp

楽しく遊ぶ
Meaning
to play or move in a lively, carefree, and energetic way
Example
The children romped happily in the garden.
子供たちは庭で楽しそうに遊んでいました。
B1 verb /rɪˈviːl/

reveal

明らかにする
Meaning
to make known or show something that was hidden
Example
The investigation revealed the truth.
調査は真実を明らかにした。
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。
C1 adjective /ˈrek.wɪ.zɪt/

Requisite

必要な; 必須の
Meaning
made necessary by particular circumstances; required
Example
Good communication skills are requisite for this job.
この仕事には良いコミュニケーションスキルが必要です。
C1 verb /rɪˈprɛs/

repress

Meaning
To restrain, suppress, or keep under control, especially emotions or desires.
Example
He tried to repress his anger during the meeting.
C1 noun /rɪdʒ/

ridge

山の稜線または頂上
Meaning
a long, narrow hilltop, mountain range, or raised strip
Example
We walked along the mountain ridge.
私たちは山脈の稜線に沿って歩きました。
B1 adjective /ˈriː.zən.ə.bəl/

Reasonable

合理的; 公正で実用的; 高すぎない; 論理的
Meaning
fair and sensible; not too expensive; logical and practical
Example
The hotel offers reasonable prices for quality accommodation.
そのホテルは品質の高い宿泊施設に対して合理的な価格を提供しています。
B2 adjective /ræʃ/

rash

軽率, 無謀
Meaning
Acting quickly without careful consideration; reckless.
Example
It was a rash decision to invest without research.
調査なしで投資するのは無謀な決断だった。
C1 verb /ræsp/

rasp

Meaning
to speak in a rough, harsh voice or to scrape with a coarse sound
Example
He rasped out a warning before collapsing.
C1 adjective /rɪˈvɜː.sə.bəl/

Reversible

可逆的な
Meaning
able to be turned the other way around; able to be undone or changed back
Example
This jacket is reversible and can be worn on both sides.
このジャケットはリバーシブルで、両面で着られます。
B2 noun /rɪˈmuː.vəl/

Removal

撤去; 除去; 解雇;
Meaning
the action of taking something away or eliminating it; dismissal from office
Example
The removal of the old furniture took all day.
古い家具の除去に一日中かかりました。
C1 verb /rɪˈbʌf/

rebuff

拒絶する
Meaning
to reject or refuse in a sharp or abrupt way
Example
She rebuffed his invitation to dinner.
彼女はディナーの招待を断った。
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 verb /rɪˈɡeɪn/

regain

回復する
Meaning
to get back something that was lost; to recover
Example
He regains his strength after the illness.
彼は病気の後、力を回復する。
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。
B2 noun /ˌrɛprɪzɛnˈteɪʃən/

representation

代表
Meaning
the action of speaking or acting on behalf of someone or something
Example
Her representation of the team was impeccable.
彼女のチームの代表は完璧でした。
C1 noun /ˌrev.əˈluː.ʃən.ər.i ˈbreɪk.θruː/

revolutionary breakthrough

革命的な発見
Meaning
A sudden, dramatic, and important discovery or development that changes everything.
Example
Robotic surgery is a revolutionary breakthrough in healthcare.
ロボット手術は医療分野での革命的な発見です。
C1 noun /ˌriː.dɪs.trɪˈbjuː.ʃən/

redistribution

再分配
Meaning
The sharing of wealth or resources more equally among society.
Example
The government introduced a redistribution policy to reduce inequality.
政府は不平等を減らすために再分配政策を導入しました。
C1 noun /ˈrɛ.trəʊ.fɪt.ɪŋ/

retrofitting

古いシステムに新しい技術や機能を追加すること
Meaning
The addition of new technology or features to older systems.
Example
The building underwent retrofitting to meet new safety standards.
その建物は、新しい安全基準に適応するためにレトロフィッティングされました。
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。
B2 noun /red liːf/

Red leaf

赤い葉
Meaning
red-colored leafy vegetable; amaranth leaves used as greens
Example
Red leaf is rich in iron and is commonly eaten in Bengali households.
赤い葉は鉄分が豊富で、ベンガルの家庭でよく食べられます。
C1 noun /ˈroʊz ˈwɔː.tər/

Rose-water

ローズウォーター
Meaning
a flavored water made by steeping rose petals in water, used in cooking and cosmetics
Example
She added a few drops of rose-water to the dessert.
彼女はデザートにローズウォーターを数滴加えました。
B2 adverb /rɪˈmɑːrkəbli/

remarkably

驚くべき方法で
Meaning
in a way that is worthy of attention or notice; surprisingly
Example
She did remarkably well in the competition.
彼女はコンペティションで驚くべき成果を上げました。
B2 noun /ˈrækɪt/

racket

ラケット / 騒音
Meaning
A piece of equipment used to hit the ball in sports like tennis or badminton; also a loud noise or an illegal scheme.
Example
He bought a new tennis racket for the match.
彼は試合のために新しいテニスラケットを買った。
C2 noun /rɪˈfɛkʃən/

refection

食事 / 反省
Meaning
a meal or the act of taking food and drink
Example
The monks gathered for their evening refection.
僧侶たちは夕食のために集まりました。
B1 verb /rʌb/

rub

こする
Meaning
to press and move something firmly against a surface; to apply pressure with movement
Example
She rubbed her hands together to keep them warm.
彼女は手をこすり合わせて暖かく保った。
B2 verb /ˈraɪpən/

ripen

幸せ
Meaning
to become or make something ready to eat or fully developed
Example
The bananas ripened quickly in the warm weather.
彼女は賞を受け取ったとき、幸せを隠せなかった。
C1 verb /rɪˈpjuː.di.eɪt/

repudiate

否定する
Meaning
to refuse to accept, recognize, or support something
Example
He repudiated the claim that he was involved in the scandal.
彼はそのスキャンダルに関与していたという主張を否定しました。
B2 adjective /raɪp/

Ripe

熟した; 食べる準備ができた
Meaning
fully developed and ready to eat; mature; ready for action or use
Example
The bananas are ripe and ready to eat.
バナナは熟して食べる準備ができています。
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。
B2 noun, verb /ræŋks/

ranks

ランク
Meaning
Positions within a group, especially in a hierarchy or organization.
Example
He quickly moved up the ranks of the army.
彼はすぐに軍隊のランクで上昇しました。
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。
C1 noun /rɪft/

rift

亀裂
Meaning
a serious break in a relationship; a split or crack
Example
A rift developed between the two friends after the argument.
議論の後、二人の友達の間に亀裂が生じた。
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。
C2 adjective /ˈrɛd.ələnt/

redolent

Meaning
having a strong pleasant smell; strongly reminiscent or suggestive of something
Example
The kitchen was redolent of spices and fresh herbs.
C1 verb /ˌriːˈvæmp/

revamp

改装
Meaning
To give a new and improved form, structure, or appearance to something.
Example
The company decided to revamp its website for a modern look.
その企業は、モダンな外観のためにウェブサイトをリヴァンプすることを決定しました。
C1 adjective /rɪˈvoʊltɪŋ/

revolting

むかつく
Meaning
extremely unpleasant or disgusting
Example
The smell of the garbage was revolting.
ごみのにおいはむかつくほどだった。
C2 noun /ˈrɪvjʊlət/

rivulet

小川
Meaning
a small stream of water; a tiny brook
Example
A rivulet ran down the hillside after the rain.
雨の後、小川が丘を下った。
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。
B2 noun rɪˈzentmənt

resentment

憤り
Meaning
Bitter indignation at having been treated unfairly.
Example
Resentment grew among the students.
学生の間で憤りが増大した。
A2 noun /ˈroʊbɒt/

robot

ロボット
Meaning
a machine capable of carrying out a complex series of actions automatically
Example
The factory uses robots to assemble cars efficiently.
工場はロボットを使って効率的に車を組み立てています。
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 noun /ˈruːmər/

rumor

噂
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。
C1 noun /rɪˈbʌtəl/

rebuttal

反論
Meaning
a statement or argument made to oppose or disprove another
Example
Her rebuttal was clear and convincing.
彼女の反論は明確で説得力がありました。
C1 adjective /ˈræspi/

raspy

ハスキー
Meaning
having a harsh, rough, or grating sound
Example
His raspy voice revealed years of smoking.
彼のハスキーな声は喫煙の年数を明らかにした。
C1 verb /ˌriːəˈdʒʌst/

readjust

再調整
Meaning
To change or move something again in order to achieve a better fit, condition, or balance.
Example
He readjusted the chair to make it more comfortable.
彼は椅子をもっと快適にするために再調整しました。
A2 noun /reɪs/

race

レース
Meaning
a competition of speed, or a group of people with similar characteristics
Example
The race was very exciting, with many competitors.
レースは非常にエキサイティングで、たくさんの競技者がいました。
A2 noun /rɪˈfrɪdʒ.ər.eɪ.tər/

Refrigerator

冷蔵庫
Meaning
an appliance for keeping food and drinks cold
Example
Please put the milk in the refrigerator to keep it fresh.
牛乳を新鮮に保つために冷蔵庫に入れてください。
B1 verb /rɪˈfɜː/

refer

参照する
Meaning
to mention or allude to something; to direct someone to a source of information
Example
Please refer to page 45 for more details.
詳細については、ページ45をご参照ください。
C1 verb /ˈrævɪdʒ/

ravage

荒廃させる
Meaning
to cause severe and extensive damage or destruction
Example
The hurricane ravaged the coastal villages.
ハリケーンは沿岸の村を荒廃させた。
C1 verb rɪˈlɪŋ.kwɪʃ

relinquish

放棄する
Meaning
To give up any authority, responsibility, or property.
Example
He decided to relinquish his position as CEO.
彼はCEOのポジションを放棄することに決めました。
C1 noun /ˈriːpər/

reaper

作物を刈り取り集める人または機械
Meaning
a person or machine that cuts and gathers crops
Example
The reaper moved slowly through the golden fields.
リーパーは金色の畑をゆっくりと進んでいきました。
C2 noun /ˌrɛtəˈrɪʃən/

rhetorician

雄弁家
Meaning
A person who is skilled in the art of rhetoric or persuasive speaking/writing.
Example
The rhetorician captivated the audience with his eloquence.
雄弁家はその雄弁さで聴衆を魅了しました。
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。
C2 adjective /rɪˈmiːdiəbl/

remediable

修正可能
Meaning
capable of being corrected or cured
Example
The mistake was serious but still remediable.
その誤りは重大でしたが、まだ修正可能でした。
B1 verb /rɪˈvaɪz/

revise

修正する
Meaning
To change, improve, or update something, especially a written work.
Example
She had to revise her essay before submission.
彼女は提出前にエッセイをリヴァイズする必要があった。
A2 verb /reɪz/

raise

上げる / 増加させる
Meaning
To lift or move something to a higher position; to increase; to bring up.
Example
She raised her hand to ask a question.
彼女は質問をするために手を上げました。
B2 verb /ˌriːjuˈnaɪt/

reunite

再会する
Meaning
to bring together again after separation
Example
The family was reunited after many years.
その家族は何年も後に再会しました。
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。
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 noun /ˈruːlɪŋ/

ruling

判決
Meaning
an official decision made by a judge or authority.
Example
The court’s ruling favored the defendant.
裁判所の判決は被告に有利でした。
C2 adjective /roʊˈtʌnd/

rotund

丸い
Meaning
round or plump in shape; full in sound
Example
The rotund cat struggled to climb the fence.
丸い猫はフェンスを登るのに苦労していた。
C1 adverb /ˈrɪdʒɪdli/

Rigidly

厳格に; 柔軟性なしで
Meaning
in a strict, inflexible manner; without compromise
Example
The rules are rigidly enforced in this institution.
この機関ではルールは厳格に適用されます。
C1 verb /rɪˈsʌsɪteɪt/

resuscitate

Meaning
to revive someone from unconsciousness or apparent death
Example
The doctors tried to resuscitate the patient after the heart attack.
B2 noun /ˈrɛnəˌsɑːns/

renaissance

ルネサンス
Meaning
a revival of art, culture, or learning; a period of renewed interest and growth
Example
The city experienced a cultural renaissance during the 1990s.
その都市は1990年代に文化的なルネサンスを経験しました。
B2 noun /reɪdʒ/

rage

怒り
Meaning
intense anger or fury
Example
She shouted in a fit of rage after hearing the news.
彼女はそのニュースを聞いて怒りの叫び声を上げました。
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。
B2 adjective /rɪˈspek.tɪv/

Respective

それぞれの; 各自の
Meaning
belonging to each individual; particular to each
Example
The students returned to their respective classrooms after lunch.
学生たちは昼食後、それぞれの教室に戻った。
B2 noun /ˌrep.ɪˈtɪʃ.ən/

Repetition

繰り返し
Meaning
the action of repeating something that has already been said or written
Example
Constant repetition helps students memorize vocabulary effectively.
継続的な繰り返しは、学生が語彙を効果的に覚えるのを助けます。
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 noun ˈredʒ.ɪ.strɑːr

registrar

レジストラー
Meaning
An official responsible for keeping records or registers.
Example
The registrar oversees all administrative tasks.
レジストラーはすべての行政業務を監督しています。
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。
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。
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。
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。
C2 adjective /ˈreə.rɪ.faɪd/

rarefied

Meaning
Of high moral, intellectual, or cultural value; distant from ordinary life.
Example
He works in the rarefied world of classical music.
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。
B2 verb /ˌriː.ɪnˈfɔːrs/

reinforce

強化する
Meaning
To strengthen or support something with additional material, people, or effort.
Example
The teacher used examples to reinforce the lesson.
教師は例を使って授業を強化しました。
A1 adverb /ˈriː.ə.li/

Really

本当に; 実際に; とても
Meaning
actually; truly; very much
Example
I really enjoyed the concert last night.
昨晩のコンサートは本当に楽しめました。
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 verb /rɪˈtriːv/

retrieve

取り戻す
Meaning
to get something back that was lost or taken; to recover
Example
She managed to retrieve her lost phone from the taxi.
彼女はタクシーから失われた電話を取り戻すことができました。
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。
C1 noun/verb /reɪn/

rein

Meaning
A strap used to control a horse; to control or guide something.
Example
The rider pulled the rein to stop the horse.
B1 verb /rɪˈspɒnd/

respond

返信する
Meaning
to give an answer or reply; to react to something
Example
Please respond to my email as soon as possible.
できるだけ早く私のメールに返信してください。
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.
A2 adjective /reər/

Rare

珍しい
Meaning
not occurring very often; uncommon or unusual
Example
It's rare to find such beautiful handmade jewelry these days.
こんな美しい手作りのジュエリーを見つけることは珍しい。
C1 adjective /riˈæk.tɪv/

Reactive

反応的; 化学的に活発
Meaning
responding to situations rather than initiating them; chemically active
Example
The company took a reactive approach to customer complaints.
会社は顧客の苦情に反応的なアプローチを採用しました。
B2 noun /ˈraɪət/

Riot

暴動; 騒乱
Meaning
a violent disturbance of the peace by a crowd; an uncontrolled outburst
Example
The peaceful protest turned into a riot when violence broke out.
平和的な抗議は暴力が起こったときに暴動に変わった。
C1 noun /rɪˈmɪt.əns/

Remittance

送金
Meaning
A sum of money sent in payment or as a gift.
Example
The country's economy benefits from expatriate remittance.
その国の経済は、移住者からの送金によって利益を得ている。
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。