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B2 adjective /ˈrʌn daʊn/

run-down

荒れ果てた
Meaning
in a poor condition; worn out or neglected
Example
They live in a run-down house at the edge of town.
彼らは町の端にある荒れ果てた家に住んでいます。
C1 noun, verb /raʊt/

rout

敗北
Meaning
A decisive defeat; to defeat completely.
Example
The army routed the enemy forces in the battle.
軍隊は戦いで敵軍を完全に打ち負かしました。
A1 adjective /ˈreɪ.di.əʊ/

radio

ラジオ
Meaning
Relating to radio waves or broadcasting.
Example
FAST is the largest radio telescope in the world.
FASTは世界最大のラジオ望遠鏡です。
C1 adjective /ˈrɪvɪtɪŋ/

riveting

魅力的な
Meaning
extremely interesting; holding the complete attention
Example
The movie was so riveting that nobody looked away.
その映画はとても魅力的で、誰も目を離すことができませんでした。
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。
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。
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 /rɪˈdaʊnd/

redound

貢献する
Meaning
to contribute greatly to a result or consequence, usually beneficial
Example
His hard work will redound to the success of the company.
彼の努力は会社の成功に貢献するでしょう。
B2 noun /'ræd.ɪʃ/

Radish

ラディッシュ
Meaning
a small pungent edible root vegetable with white or red skin
Example
The farmer harvested fresh radishes from the garden.
農家は庭から新鮮なラディッシュを収穫しました。
C2 noun /rʌmp/

Rump

尻; お尻; 背中の下部
Meaning
the hindquarters or buttocks; the lower back area
Example
The horse injured its rump during the fall.
その馬は転倒した際にお尻を痛めました。
C1 adjective /rɪˈɡrɛtfəl/

regretful

後悔している
Meaning
feeling or showing sadness or disappointment about something that has happened or been done
Example
She gave him a regretful smile as she turned away.
彼女は振り返りながら後悔している笑顔を彼に向けた。
C1 verb /rɪˈpiːl/

repeal

Meaning
To officially cancel or revoke a law or decision.
Example
The government decided to repeal the outdated law.
C1 noun /rəʊˈbɒt.ɪk ˈsɜː.dʒər.i/

robotic surgery

ロボット手術
Meaning
Surgery performed with the assistance of robotic systems to enhance precision and reduce invasiveness.
Example
Robotic surgery enhances precision in complex procedures.
ロボット手術は複雑な手順で精度を高めます。
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 verb /rɪˈvoʊlt/

revolt

反乱する
Meaning
to rebel against authority; to feel disgust
Example
The people revolted against the corrupt government.
人々は腐敗した政府に反乱を起こしました。
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。
B2 noun /ˈrɛzərvwɑːr/

reservoir

貯水池
Meaning
A large natural or artificial lake used as a source of water supply.
Example
The city built a new reservoir to ensure enough drinking water for its residents.
その都市は住民に十分な飲料水を確保するために新しい貯水池を建設した。
C2 noun /ˈræʃənəlɪzəm/

rationalism

合理主義
Meaning
a belief or theory that opinions and actions should be based on reason and knowledge rather than religious belief or emotion
Example
Rationalism emphasizes logic and reasoning over faith.
合理主義は信仰よりも論理と推論を強調します。
B2 verb /ˌriːkriˈeɪt/

recreate

再創造する
Meaning
to create or produce something again, especially a new version of something lost or destroyed
Example
The team recreated the lost dataset from backups.
チームはバックアップから失われたデータセットを再作成しました。
C1 noun /rɪˈmɛmbrəns/

remembrance

記憶
Meaning
the act of remembering or honoring someone or something
Example
A service was held in remembrance of the fallen soldiers.
戦死した兵士たちを記憶するための式典が行われた。
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。
C2 adjective /ˈrɛkənˌsaɪləbl̩/

reconcilable

Meaning
Capable of being resolved or made consistent.
Example
Their differences are reconcilable with honest communication.
B1 adverb /ˈrʌfli/

Roughly

おおよそ; 粗暴または暴力的な方法で
Meaning
approximately; in a harsh or violent way
Example
The project will take roughly three months to complete.
このプロジェクトはおおよそ3ヶ月かかります。
B2 adjective /rɪˈlʌktənt/

Reluctant

消極的な; ためらう; 何かをすることに抵抗がある;
Meaning
unwilling; hesitant; disinclined to do something;
Example
She was reluctant to share her personal information.
彼女は個人情報を共有することに消極的でした。
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 /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。
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。
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。
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。
C1 adjective /ˈraʊzɪŋ/

rousing

興奮させる
Meaning
Exciting, inspiring, or stirring.
Example
The speaker delivered a rousing speech that moved the audience.
スピーカーは聴衆を感動させる興奮させるスピーチをしました。
A2 noun /rɪˈleɪ.ʃən.ʃɪp/

Relationship

関係
Meaning
the way two people or groups feel and behave towards each other; a connection between two things
Example
They have a very close relationship.
彼らは非常に親密な関係を持っています。
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 /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 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。
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。
C1 adjective /ˈraɪ.tʃəs/

Righteous

正義の; 公正な; 道徳的な
Meaning
morally right or justifiable; virtuous; having strong moral principles
Example
She felt righteous anger at the unfair treatment of workers.
彼女は労働者の不当な扱いに対して正義の怒りを感じました。
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.
C2 adjective /rɪˈzɪstləs/

resistless

抗えない
Meaning
Impossible to resist; having an overpowering effect.
Example
She felt a resistless urge to laugh at the joke.
彼女はジョークで笑いたいという抗えない衝動を感じた。
C1 verb /ˌriːˈkɒn.stɪ.tʃuːt/

reconstitute

再構成する
Meaning
to restore something to its original form or state; to reassemble
Example
The group was reconstituted after the leader returned.
リーダーが戻った後、グループは再構成されました。
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。
A2 verb /rɪˈsiːv/

receive

受け取る
Meaning
to get or accept something given; to welcome
Example
She receives a gift from her friend.
彼女は友達から贈り物を受け取ります。
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。
B1 adjective /ˈrʊr.əl/

Rural

田舎の
Meaning
relating to the countryside; characteristic of farming or country life
Example
She grew up in a rural area far from the city.
彼女は街から遠く離れた田舎の地域で育ちました。
B2 verb /rɪˈvɜːrt/

revert

戻る
Meaning
to return to a previous state, condition, or practice
Example
The system will revert to its original settings after the update.
システムは更新後、元の設定に戻ります。
C2 noun /ˈruː.mɪ.nənt/

ruminant

反芻動物
Meaning
a cud-chewing mammal, such as a cow or sheep
Example
Cows are ruminants that chew cud.
牛は反芻動物で、食べ物を再度咀嚼します。
C1 verb /ˈrɪdɪkjuːl/

ridicule

嘲笑する
Meaning
To make fun of someone or something in a cruel or dismissive way.
Example
He was ridiculed for his strange ideas.
彼は奇妙な考えのために嘲笑されました。
C1 phrase ˈriː.dʒən.əl ˈfɔː.rəm

regional forum

地域フォーラム
Meaning
A meeting or conference where representatives from countries or organizations in a specific geographical area discuss issues of common interest.
Example
The Regional Forum discussed deforestation impacts.
地域フォーラムでは、森林伐採の影響について議論されました。
C1 verb rɪˈplɛn.ɪʃ

replenish

補充する
Meaning
Fill something up again.
Example
Drinking water helps replenish lost fluids in the body.
水を飲むことは、体内で失われた液体を補充するのに役立ちます。
C1 noun rɪˈdɛmpʃən

redemption

贖い
Meaning
The action of saving or being saved from sin, error, or evil.
Example
The story highlights the theme of redemption.
その物語は償いのテーマを強調しています。
C2 noun /ˌrɛtroʊˈɡrɛʃən/

retrogression

後退
Meaning
a return to a worse or less developed state
Example
The country experienced economic retrogression after the crisis.
国は危機後、経済的な後退を経験しました。
B2 noun /ˈriːteɪlər/

retailer

小売業者
Meaning
a person or business that sells goods to consumers rather than to other businesses
Example
The retailer offers discounts on electronic products.
小売業者は電子製品に割引を提供しています。
B2 noun /rɪˈfreʃ.mənt/

Refreshment

軽食
Meaning
food and drink that is served as a light meal; something that refreshes
Example
We served light refreshments after the meeting.
会議の後、軽食を提供しました。
C2 noun /ˌrækənˈtɜːr/

Raconteur

幸せ
Meaning
a person who tells anecdotes in a skillful and amusing way
Example
The old man was a gifted raconteur who entertained everyone with his stories.
彼女は賞を受け取ったとき、喜びを隠せなかった。
C1 verb /rɪˈdiːm/

redeem

償う
Meaning
to compensate for faults or mistakes; to exchange something for value
Example
He managed to redeem his reputation after the scandal.
彼はスキャンダル後に自分の評判を回復しました。
B2 verb /ˌriːəˈʃʊr/

reassure

安心させる
Meaning
to say or do something to remove someone's doubts or fears
Example
The teacher reassured the students before the exam.
教師は試験前に生徒を安心させました。
C1 verb /ˈrɪvɪt/

rivet

リベットで固定する / 注意を引く
Meaning
to fasten or secure with a rivet; to hold someone’s attention firmly
Example
The craftsman riveted the metal plates together.
職人は金属の板をリヴェットで留めました。
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。
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 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。
C1 verb /ˈreɪdieɪt/

radiate

放射する
Meaning
to emit energy or light; to spread out from a center
Example
The fireplace radiates warmth throughout the room.
暖炉は部屋全体に暖かさを放射します。
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。
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 noun /rɛlm/

realm

Meaning
A kingdom or domain; a field or area of activity or interest.
Example
He is well known in the realm of science.
C1 adjective /ˈreɡ.jʊ.lə.tər.i/

Regulatory

規制
Meaning
Having the power to control or govern something through rules and regulations.
Example
The government enforces regulatory policies for financial stability.
政府は金融安定性のために規制政策を実施しています。
C1 adjective /ˈriː.fleks/

Reflex

反射
Meaning
an action performed without conscious thought; relating to reflection
Example
The doctor tested her reflex response by tapping her knee.
医師は彼女の膝を軽く叩いて反射的な反応をテストしました。
C2 noun /ˌrɛprəˈbeɪʃən/

reprobation

Meaning
Strong disapproval or condemnation; rejection by God as beyond salvation.
Example
The teacher’s face showed clear reprobation at the student’s rude remark.
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。
B1 noun /ˌrɛzəˈluːʃən/

resolution

解決, 決議
Meaning
The action of solving a problem, dispute, or contentious matter.
Example
The resolution of the issue requires careful planning and action.
問題の解決には慎重な計画と行動が必要です。
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。
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 /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。
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 noun /red ˌəʊ.liˈæn.dər/

Red oleander

赤いオリンダー
Meaning
a poisonous flowering shrub with bright red or pink flowers
Example
The red oleander blooms throughout the summer months.
赤いオリンダーは夏の数ヶ月間咲きます。
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。
C1 noun /ˈrɪpəl/

Ripple

波紋
Meaning
a small wave on the surface of water; a spreading effect or influence
Example
The stone created ripples across the calm pond.
石が静かな池に波紋を作った。
C1 verb /ˌriːhəˈbɪlɪteɪt/

rehabilitate

Meaning
to restore someone to health, normal life, or a good condition after illness, injury, or imprisonment
Example
The clinic helps rehabilitate injured athletes.
C2 noun /ˈrɛvəlri/

revelry

祭り
Meaning
Lively and noisy festivities, especially involving drinking and dancing.
Example
The sound of revelry could be heard throughout the night.
一晩中、祭りの音が聞こえていました。
A1 noun /ruːm/

room

部屋
Meaning
A space within a building enclosed by walls, floor, and ceiling
Example
She decorated her room with bright colors.
彼女は明るい色で自分の部屋を飾りました。
B2 noun rɪsk ˈfæktər

risk factor

リスク要因
Meaning
Something that increases the likelihood of developing a disease or condition
Example
Water pollution is a significant risk factor for health.
水質汚染は健康にとって重要なリスク要因です。
C1 adjective /rɪˈtɔːrɪkəl/

rhetorical

修辞的
Meaning
relating to the art of effective or persuasive speaking or writing; often a question asked to make a point rather than get an answer
Example
He asked a rhetorical question during the debate.
彼は討論中に修辞的な質問をした。
C1 verb /ˌrɛzəˈrɛkt/

resurrect

復活させる
Meaning
To bring back to life or revive something from the past.
Example
The director decided to resurrect the old play for a new audience.
監督は新しい観客のために古い劇を復活させることに決めました。
B2 noun /ˌrezəˈveɪʃən/

Reservation

予約
Meaning
the action of reserving something; an arrangement whereby something is reserved for a particular person; a qualification to an expression of agreement or approval
Example
I made a reservation at the restaurant for tonight.
今夜のレストランの予約をしました。
C1 verb /rɪˈpʌls/

repulse

撃退する / 嫌悪感を引き起こす
Meaning
to drive back an attack or attacker by force; to cause intense dislike or disgust
Example
The army managed to repulse the enemy attack.
軍隊は敵の攻撃を撃退することに成功した。
B1 noun /rɪˈsep.ʃən/

Reception

歓迎; 受け入れ; イベント;
Meaning
the action of receiving something or someone; a formal social occasion held to welcome someone
Example
The wedding reception was held at a beautiful hotel.
結婚式のレセプションは美しいホテルで行われました。
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。
C1 noun /riːk/

Reek

悪臭がする; 不快または望ましくない印象を与える
Meaning
to have a very unpleasant smell; to give a strong impression of something unpleasant or undesirable
Example
The garbage can reeks of rotten food.
ゴミ箱は腐った食べ物の臭いがする。
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 adjective /ˈreɪ.si/

racy

刺激的
Meaning
Lively, entertaining, or slightly shocking (especially in a sexual way).
Example
The novel was full of racy dialogues.
その小説は刺激的な対話で満ちていた。
C1 noun /ˈrʌfiən/

Ruffian

暴力的な人物; 不良;
Meaning
a violent person, especially one involved in crime; a brutal or lawless person
Example
The ruffian threatened the shopkeeper for money.
不良は店主を金のために脅した。
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。
B1 noun /rɪˈkʌvəri/

recovery

回復
Meaning
the process of recovering or returning to a normal state
Example
The patient is in recovery after the surgery.
患者は手術後、回復中です。
C1 noun /rɪˈpɛərə/

repairer

修理人
Meaning
a person whose job is to fix damaged or broken things
Example
The repairer fixed the broken washing machine quickly.
修理人は壊れた洗濯機をすぐに直した。
B2 verb /riːp/

reap

収穫する
Meaning
to cut or gather a crop; to receive as a consequence of actions
Example
Farmers reap wheat in the late summer.
農家は晩夏に小麦を収穫します。
B2 noun /ˈrɪk.ʃɔː/

Rickshaw

リクシャ
Meaning
a light two-wheeled passenger vehicle drawn by one or more people
Example
We took a rickshaw to reach the busy marketplace.
忙しい市場に到着するためにリクシャを利用しました。
C1 noun /ˈrɪɡər/

rigor

厳格さ
Meaning
strictness, severity, or demanding conditions
Example
The training was carried out with great rigor.
訓練は大変厳格に行われました。
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。
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。
C2 adjective /ˈrɛɡnənt/

regnant

統治している
Meaning
Reigning; currently holding power, authority, or dominance.
Example
The regnant queen introduced several reforms during her reign.
統治している女王は、彼女の統治期間中にいくつかの改革を導入しました。
B1 noun rɪˈdʌk.ʃən

reduction

削減
Meaning
The action or fact of making a specified thing smaller or less in amount, degree, or size.
Example
Greenhouse gas reduction is a primary global goal.
温室効果ガスの削減は主要な地球規模の目標です。
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 noun /rɪˈmɔːrs/

Remorse

後悔
Meaning
deep regret or guilt for a wrong committed; bitter regret for something done
Example
He felt deep remorse for his actions.
彼は自分の行動に対して深い後悔を感じていた。
C2 verb /rɔɪl/

roil

かき乱す
Meaning
to make a liquid muddy or disturbed; to cause agitation or disorder
Example
The constant protests roiled the city streets.
絶え間ない抗議が街の通りをかき乱した。
C2 noun /rɪˈfrɪndʒənsi/

refringency

屈折率
Meaning
The ability of a substance to bend light; refractive power.
Example
Glass has a higher refringency than water.
ガラスは水よりも高いリフリンジェンシーを持っています。
C1 noun /ræmˈbuːtən/

Rambutan

ランブータン
Meaning
a tropical fruit with red spiky skin and white translucent sweet flesh similar to litchi
Example
The rambutan looks scary with its hairy skin but tastes very sweet inside.
ランブータンは毛皮のような皮で怖そうに見えますが、中はとても甘いです。
B2 noun /ˌriː.ɪnˈfɔːrs.mənt/

reinforcement

強化
Meaning
Strengthening or supporting something, especially behavior or learning.
Example
Positive reinforcement helps in learning.
積極的な強化は学習に役立ちます。
C2 adjective rɪˈtɛn.tɪv

retentive

記憶力が強い
Meaning
Having strong memory or the ability to retain information for a long time.
Example
Students with a retentive memory excel in academics.
記憶力が強い学生は学業で優れています。
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。
C1 noun /rɪˈdʒɔɪsɪŋ/

rejoicing

喜び
Meaning
The action of showing great joy or happiness
Example
There was much rejoicing after the victory.
勝利後、多くの喜びがありました。
C1 adjective /ˈrɔːkəs/

raucous

騒々しい, うるさい
Meaning
loud, harsh, and unpleasant sound or behavior
Example
The crowd became raucous after the team scored.
チームがゴールを決めると、群衆は騒がしくなった。
A2 verb /rɪˈpleɪs/

replace

交換する
Meaning
to take the place of something or someone; to put something new in place of something old
Example
He decided to replace the broken lamp with a new one.
彼は壊れたランプを新しいものと交換することに決めました。
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。
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 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。
B2 noun ˈrɛstɪŋ pleɪs

resting place

安息地
Meaning
A place where someone or something rests, especially a burial site.
Example
The resting place of the martyrs is near the river.
殉教者の安息地は川の近くにあります。
C2 noun /ˈrɒndoʊ/

rondo

音楽作品(繰り返しのテーマを持つ)
Meaning
a musical composition with a recurring leading theme
Example
The pianist ended the recital with a lively rondo.
ピアニストは生き生きとしたロンドでリサイタルを終えました。
C1 verb /rɪˈbjuːk/

rebuke

叱る
Meaning
to criticize or scold sharply; to express disapproval
Example
The teacher had to rebuke the student for cheating.
先生は cheating のため学生を叱らなければならなかった。
A1 noun, adjective, adverb /raɪt/

right

権利
Meaning
something that is morally good, fair, or just; or a legal/entitled claim
Example
Everyone has the right to free speech.
誰もが自由な言論の権利を持っています。
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。
B2 noun /ˈreɪn.dʒər/

ranger

レンジャー
Meaning
A person responsible for protecting and managing forests, parks, or natural areas.
Example
The park ranger guided the tourists through the forest trail.
公園のレンジャーは観光客を森の小道を案内しました。
A2 adverb /ˈriː.sənt.li/

Recently

最近
Meaning
in the recent past; not long ago
Example
I recently moved to a new apartment.
私は最近新しいアパートに引っ越しました。
B1 noun /rɪˈsɔːrs/

resource

資源
Meaning
A supply of materials, money, or assets that can be used when needed.
Example
Water is a vital natural resource.
水は重要な自然資源です。