roil
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
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。
C1 adjective /ræmˈbʌŋk.ʃəs/

rambunctious

騒々しい
Meaning
boisterous, energetic, and difficult to control.
Example
The rambunctious children filled the house with noise.
騒々しい子供たちが家を騒音で満たしました。
B2 noun, verb /ˈriːteɪl/

retail

小売
Meaning
the sale of goods to the public in small quantities for use or consumption rather than for resale
Example
The company specializes in the retail of clothing and accessories.
この会社は衣類とアクセサリーの小売を専門としています。
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 /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。
C1 noun /ˈrɛl.ɪk/

relic

遺物
Meaning
an object surviving from an earlier time, often of historical or religious interest
Example
The museum displayed relics from the ancient civilization.
博物館には古代文明の遺物が展示されていました。
B2 adjective /ˈrʌs.ti/

Rusty

錆びた; 練習不足; 最近の練習不足による障害
Meaning
affected by rust; out of practice; impaired by lack of recent practice
Example
My piano skills are rusty after not playing for years.
何年もピアノを弾いていなかったので、私のピアノのスキルは錆びついています。
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 adjective /ˈroʊziət/

roseate

バラ色の、楽観的な
Meaning
Having a pink color; optimistic or idealistic.
Example
She looked at the future with roseate optimism.
彼女はローズ色の楽観主義で未来を見ました。
B2 verb /ˌriːˈbɪld/

rebuild

再建する
Meaning
to build something again after it has been damaged or destroyed
Example
The villagers worked together to rebuild the bridge after the flood.
村人たちは洪水の後、橋を再建するために協力しました。
A1 adjective /ˈrɛd.i/

ready

準備ができた
Meaning
Prepared or available for use or action.
Example
She was ready to leave for the airport.
彼女は空港に行く準備ができていた。
B2 verb /rɪˈvɜːs/

reverse

反転する
Meaning
to change something to the opposite direction, position, or result
Example
She quickly reversed the car out of the driveway.
彼女はすぐに車をドライブウェイからバックさせました。
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。
B2 verb /rɪˈteɪn/

retain

保持する
Meaning
to keep possession of something
Example
The company decided to retain its experienced employees.
会社は経験豊富な従業員を保持することに決めました。
B2 noun /ˈrɛlɪvənsi/

relevancy

関連性
Meaning
the quality of being closely connected or appropriate
Example
The professor questioned the relevancy of the example to the topic.
教授はその例がトピックに関連しているかどうかを疑問視しました。
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。
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 /rɪˈsɜːrdʒ/

resurge

再興
Meaning
To rise, increase, or become active again after a decline.
Example
Interest in traditional crafts has begun to resurge.
伝統工芸に対する関心が再び高まり始めています。
A1 noun /ˈrɪv.ər/

River

川
Meaning
a large natural stream of water flowing in a channel to the sea, a lake, or another river
Example
The river flows through the valley and into the ocean.
川は谷を流れ、海に注ぎ込む。
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 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。
C2 verb /rɪˈmɒnstreɪt/

remonstrate

抗議する
Meaning
To make a forceful protest or objection.
Example
Citizens remonstrated against the new tax policy.
市民たちは新しい税制政策に抗議した。
B2 adjective ˌriːprəˈdʌktɪv

reproductive

繁殖に関する
Meaning
Relating to the reproduction of offspring.
Example
The reproductive cycle of pests can cause rapid infestations.
害虫の生殖サイクルは迅速な感染を引き起こす可能性があります。
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 noun /rɪˈkɜr.əns/

Recurrence

再発
Meaning
the fact of something happening again; an instance of something happening again
Example
The doctor was concerned about the recurrence of the patient's symptoms.
医師は患者の症状の再発について懸念していました。
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。
B2 noun /ˌref.jʊˈdʒiː/

Refugee

難民
Meaning
a person who has been forced to leave their country in order to escape war, persecution, or natural disaster
Example
The refugee camp provided temporary shelter for thousands of displaced families.
難民キャンプは、何千人もの避難した家族に一時的な避難所を提供しました。
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 adjective /ˈrʌɡ.ɪd/

Rugged

でこぼこで不規則な; 不規則な表面を持つ; 強くて丈夫な
Meaning
rough and uneven; having a rough irregular surface; tough and strong
Example
The hikers crossed the rugged mountain terrain.
ハイカーたちは荒れた山岳地帯を越えた。
B2 adjective /ˈrɪɡ.ər.əs/

rigorous

厳格な
Meaning
Extremely thorough and demanding in analysis or practice.
Example
A rigorous study plan helps students achieve better results.
厳格な学習計画は、学生がより良い結果を得るのに役立ちます。
B2 noun /ˈraɪdər/

rider

ライダー
Meaning
A person who rides a horse, bicycle, motorcycle, or other vehicle.
Example
The rider fell off the horse.
ライダーは馬から落ちました。
B2 noun rɪˈtɛnʃən

retention

保持
Meaning
The continued possession, use, or control of something
Example
The retention of information is essential for academic success.
情報の保持は学問的成功のために重要です。
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。
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 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 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。
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。
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 verb/noun /ˈrɛlɪʃ/

relish

楽しむ / 調味料
Meaning
to greatly enjoy; also a condiment or sauce
Example
She relished the opportunity to travel abroad.
彼女は海外旅行の機会を大いに楽しんでいました。
B2 noun /rʌst/

Rust

錆
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。
B2 verb rɪˈzaɪn

resign

辞任する
Meaning
Voluntarily leave a job or other position.
Example
Ministers were forced to resign.
大臣たちは辞任を余儀なくされました。
C2 verb /rɪˈkwaɪt/

requite

返す
Meaning
to return or repay a favor, service, or feeling
Example
She requited his kindness with a thoughtful gift.
彼女は彼の親切に思慮深い贈り物で報いました。
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 /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。
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。
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 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。
C2 noun /raɪm/

rime

霜
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 /rɪˈspɒndənt/

respondent

回答者
Meaning
A person who replies to something, especially in a survey or legal case
Example
The survey had over 1,000 respondents.
調査には1000人以上の回答者がいました。
C2 noun, adjective, verb /ˈrɛprəˌbeɪt/

reprobate

Meaning
A person of immoral character; to express disapproval of; morally corrupt.
Example
The old reprobate spent his days gambling and drinking.
C2 noun /ˈrɛv.ər.i/

reverie

白昼の夢; 夢想
Meaning
A state of being pleasantly lost in one's thoughts; a daydream.
Example
Lost in reverie, he didn't hear his name being called.
夢想にふけっているため、彼は名前が呼ばれるのを聞かなかった。
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。
C2 noun /riːm/

ream

リーム
Meaning
A large quantity of paper (typically 500 sheets); informally, a large amount of something.
Example
The office ordered ten reams of paper.
オフィスは10リームの紙を注文した。
B2 adverb /ˈræp.ɪd.li/

Rapidly

速やかに; 急速に
Meaning
at a fast speed; quickly
Example
The company is rapidly expanding into new markets.
会社は新しい市場に急速に拡大しています。
B2 noun /ˈrɛfjuːdʒ/

refuge

避難所
Meaning
a place that provides shelter or protection from danger or distress
Example
The villagers took refuge in the temple during the storm.
村人たちは嵐の間、寺院に避難した。
B2 verb /rɪˈtriːt/

retreat

撤退する
Meaning
to move back or withdraw from a position or situation
Example
The soldiers had to retreat after losing the battle.
兵士たちは戦いに負けた後、撤退しなければならなかった。
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.
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。
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。
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。
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。
B1 noun /ˈrɪðəm/

rhythm

リズム
Meaning
a strong, regular, repeated pattern of movement or sound
Example
The rhythm of the music made everyone want to dance.
音楽のリズムはみんなを踊りたくさせた。
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。
C1 adjective /ˈræmpənt/

rampant

蔓延する
Meaning
existing or spreading unchecked, often in an undesirable way
Example
Corruption was rampant in the city administration.
腐敗は市の行政で蔓延していた。
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 /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。
C1 noun /ˈrʌbəl/

rubble

瓦礫
Meaning
Broken stone, bricks, or debris from a collapsed building or structure.
Example
The rescue team searched through the rubble after the earthquake.
地震後、救助隊は瓦礫の中を探しました。
A2 noun /ruːf/

roof

屋根
Meaning
the top covering of a building or vehicle
Example
The roof of the house needs to be repaired.
家の屋根は修理が必要です。
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 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。
B2 adjective /ˈruː.mi/

Roomy

広々とした; 広いスペースのある
Meaning
spacious; having a lot of room
Example
The apartment is very roomy with spacious bedrooms.
アパートメントは広々としており、広いベッドルームがあります。
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 /ˈreɪn.dʒɪŋ/

ranging

変動する
Meaning
Extending or varying between limits.
Example
The temperatures are ranging from 15 to 30 degrees this week.
今週の気温は15度から30度の間で変動しています。
C2 noun /ˈriːdʒənt/

regent

摂政
Meaning
a person who rules in place of a monarch when the monarch is absent or too young
Example
The prince acted as regent until the king came of age.
王子は王が成人するまで摂政として行動した。
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 /ˈrʊki/

rookie

初心者
Meaning
a person who is new to an activity or organization; a beginner
Example
The rookie policeman made a few mistakes on his first day.
新米警官は初日にいくつかのミスを犯しました。
C1 noun /rɪˈsaɪtl/

recital

リサイタル
Meaning
A performance of music, dance, or poetry, usually by a soloist.
Example
She gave a piano recital at the concert hall.
彼女はコンサートホールでピアノのリサイタルを行いました。
B1 verb /ˈreskjuː/

rescue

救助する
Meaning
to save someone or something from danger or harm
Example
The firefighters rescued the cat from the tree.
消防士は木から猫を救助しました。
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。
C2 adjective /rɪˈsplɛndənt/

resplendent

輝かしい
Meaning
Shining brilliantly; dazzling in appearance or effect
Example
The bride looked resplendent in her wedding gown.
花嫁はウェディングドレスで輝いて見えました。
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。
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。
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。
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。
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 noun /rəˈpɪdəti/

rapidity

迅速さ
Meaning
The quality of moving or happening quickly; swiftness or speed.
Example
The rapidity of technological change is astonishing.
技術的な変化の速さは驚くべきものです。
C1 noun /ˌrɛspɪˈreɪʃən/

respiration

Meaning
The process of breathing or the exchange of gases in living organisms.
Example
Respiration is essential for all living beings.
C1 adjective /ˈraɪtfəl/

rightful

正当な
Meaning
having a legitimate or just claim; proper or lawful
Example
She is the rightful owner of the property.
彼女はその財産の正当な所有者です。
B2 verb /rɪˈzɪst/

resist

抵抗する
Meaning
to oppose or fight against; to withstand
Example
He could not resist the temptation.
彼は誘惑に抵抗できませんでした。
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 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 noun /rɪˈflɛktər/

reflector

反射器
Meaning
A surface or device that reflects light, heat, or sound, often used to direct beams or improve visibility.
Example
The cyclist attached a red reflector to the back of his bike for safety.
自転車のライダーは安全のために自分の自転車の後ろに赤い反射器を取り付けました。
C1 noun /ˈreɪdiəns/

radiance

輝き
Meaning
the quality of shining with bright light; a glowing or beaming quality
Example
Her face was filled with radiance after hearing the good news.
良いニュースを聞いた後、彼女の顔は輝きで満ちていました。
C1 noun /rɪˈpraɪ.zəl/

Reprisal

報復
Meaning
an act of retaliation; revenge taken for an injury or wrong
Example
The attack was carried out as a reprisal for the earlier bombing.
この攻撃は以前の爆撃に対する報復として行われました。
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。
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 rəʊlz

Roles

役割
Meaning
A person's or thing's function in a particular situation.
Example
Defined roles improve team performance.
定義された役割はチームのパフォーマンスを向上させる。
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.
A2 verb /rɪŋ/

ring

鳴る
Meaning
to make a clear sound like a bell; to call by telephone
Example
The bell rings every hour.
鐘は毎時鳴る。
C2 adjective /rɪˈfjuː.tə.bəl/

Refutable

反証可能
Meaning
capable of being proven wrong or false; able to be disproved
Example
His theory was refutable because it could be tested experimentally.
彼の理論は実験的にテストできるので反証可能でした。
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。
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.
C1 noun /ˈrɛz.ə.nəns/

resonance

共鳴
Meaning
A deep, reverberating sound or a quality of evoking response.
Example
His speech had a deep resonance with the audience.
彼のスピーチは観客に深い共鳴を与えた。
B1 noun /rɪˈpɔːtɪŋ/

reporting

報道
Meaning
the act of giving news or information about something
Example
Good reporting is essential for public awareness.
良い報道は公共の認識にとって不可欠です。
B2 noun rɪˈzɪl.i.əns

resilience

レジリエンス
Meaning
The ability to recover quickly from difficulties; toughness.
Example
Testing the resilience of wood is crucial.
木材のレジリエンスをテストすることは非常に重要です。
A2 noun /ruːlz/

rules

ルール
Meaning
explicit principles or regulations governing conduct or procedure within a particular area of activity
Example
The teacher reminded the students to follow the classroom rules.
先生は生徒にクラスのルールに従うように注意しました。
C1 noun /rɪˈtriː.vəl/

retrieval

回復
Meaning
The process of getting something back, especially from storage or memory.
Example
The brain's retrieval system helps recall past experiences.
脳のリトリーバルシステムは過去の経験を思い出すのに役立ちます。
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。
C2 noun /ˈræpsədi/

rhapsody

高揚した歌/賛美
Meaning
an expression of great enthusiasm or an epic musical composition
Example
The singer’s performance was a rhapsody of emotions.
歌手のパフォーマンスは感情のラプソディでした。
C2 noun /rɪˈvaɪlər/

reviler

侮辱者
Meaning
a person who criticizes or insults others abusively
Example
He was known as a reviler of all who opposed him.
彼は自分に反対する全ての人々を侮辱する者として知られていました。
B1 noun /rɪsk/

Risk

リスク
Meaning
a situation involving exposure to danger; the possibility of something bad happening
Example
Taking this investment carries a high risk of losing money.
この投資には高いリスクが伴い、資金を失う可能性があります。
C1 noun /ˈræftər/

rafter

小屋の梁
Meaning
One of the sloping beams that supports a roof.
Example
The old barn’s rafters were exposed.
古い納屋の小屋の梁がむき出しになっていました。
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。
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。
C1 verb /ˈrevəl/

revel

楽しむ
Meaning
to enjoy oneself in a lively and noisy way; to take great pleasure in
Example
They revel in their success.
彼らは成功を楽しんでいます。
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。
A2 adjective /riːl/

Real

本物の; 真正の; 偽物ではない
Meaning
actually existing; genuine; not imaginary or fake
Example
This is a real diamond, not a fake one.
これは本物のダイヤモンドです。偽物ではありません。
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 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。
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。
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。