C1 verb ˈɔːr.kɪ.streɪt

orchestrate

調整する

Meaning

To plan or coordinate the elements of (a situation) to produce a desired effect, especially surreptitiously.

Example

He skillfully orchestrated the entire event.

彼は巧妙に全体のイベントを調整しました。

B2 verb /əˈblaɪdʒ/

oblige

義務付ける

Meaning

to compel or require someone to do something; to help or do a favor

Example

I would be happy to oblige you with the information you need.

必要な情報を提供してお手伝いできれば嬉しいです。

A2 verb /ˈɔːfər/

offer

申し出る

Meaning

to present something for acceptance or rejection; to propose

Example

She offered to help with the project.

彼女はプロジェクトを手伝うと申し出た。

B2 noun /ˈɒpəreɪtər/

operator

オペレーター

Meaning

a person who operates equipment, a business, or controls something

Example

The machine operator ensured that everything ran smoothly.

機械オペレーターは、すべてがスムーズに動作することを確認しました。

A2 adverb; noun /ˌaʊtˈdɔːrz/

outdoors

屋外で

Meaning

outside a building; the natural environment outside

Example

We spent the whole afternoon outdoors enjoying the fresh air.

私たちは午後ずっと屋外で新鮮な空気を楽しみました。

A2 modal verb /ɔːt/

ought

べき

Meaning

Used to indicate duty, correctness, or moral obligation.

Example

You ought to respect your elders.

あなたは年長者を尊敬すべきです。

B1 noun /aʊl/

Owl

フクロウ

Meaning

a nocturnal bird of prey with large eyes and a hooked beak

Example

The owl hooted softly in the darkness of the forest.

フクロウは森の暗闇で静かに鳴いた。

C1 noun /ˈɑːdəsi/

odyssey

長い旅

Meaning

a long, adventurous journey; a series of experiences

Example

Her career has been an odyssey of challenges and achievements.

彼女のキャリアは挑戦と成果の長い旅でした。

B2 noun /ˈɒkjʊpənt/

occupant

乗客

Meaning

A person who resides in or is present in a house, vehicle, seat, or place.

Example

The car had three occupants at the time of the accident.

事故の時、車には三人の乗客がいました。

B2 noun /ˈaʊtˌbreɪk/

outbreak

発生

Meaning

a sudden start or occurrence of something unpleasant, like disease or violence

Example

There was an outbreak of flu in the city.

街でインフルエンザが発生した。

B2 adjective /ˈɔː.də.li/

Orderly

整然とした; 系統的な; 平和的な

Meaning

well-organized; systematic; peaceful

Example

Please keep your desk orderly and clean.

デスクを整然とした状態できれいに保ってください。

C1 verb /aʊst/

oust

追放する

Meaning

To remove someone from a position or place of power or authority.

Example

The rebels ousted the dictator from power.

反乱者は独裁者を権力から追い出しました。

B1 noun /ˈɔr.ə.ʒɪn/

Origin

起源

Meaning

the point or place where something begins, arises, or is derived; the source

Example

Scientists are studying the origin of the universe.

科学者たちは宇宙の起源を研究しています。

C1 verb /ˌoʊvərˈrʌn/

overrun

侵略する

Meaning

to spread over or occupy completely; to exceed a limit or time

Example

The garden was overrun with weeds.

庭は雑草に覆われていた。

B1 adjective /əˈbiː.di.ənt/

Obedient

従順な

Meaning

willing to comply with orders or instructions; submissive

Example

The obedient student always follows the teacher's instructions.

従順な生徒はいつも先生の指示に従う。

C2 noun (plural) /ˈɔːrdʒiːz/

orgies

オルギー

Meaning

Wild gatherings involving excessive indulgence in food, drink, or sexual activity.

Example

The ancient Romans were infamous for their lavish feasts and orgies.

古代ローマ人は豪華な宴会とオルギーで悪名高かった。

B2 noun /ˈɑp.tə.mɪst/

Optimist

楽観主義者

Meaning

a person who tends to be hopeful and confident about the future; someone who sees the good side of things

Example

As an optimist, she always believed things would improve.

楽観主義者として、彼女は常に物事が改善されると信じていました。

C2 noun /ˈaʊtˌrɪɡər/

outrigger

安定構造

Meaning

a projecting structure on a boat, used for stability, or a boat fitted with such support

Example

The fisherman paddled his outrigger canoe across the lagoon.

漁師はアウトリガー付きのカヌーをラグーンを越えて漕ぎました。

B2 adjective /ˌɔːɡənaɪˈzeɪʃənəl/

organizational

組織的

Meaning

relating to the structure or arrangement of a company or group

Example

He works on improving the organizational structure of the company.

彼は会社の組織構造を改善するために働いています。

C1 adjective /ˈɒm.ɪ.nəs/

Ominous

不吉な; 脅威の

Meaning

giving the impression that something bad will happen; threatening; foreboding

Example

The dark clouds looked ominous before the storm.

嵐の前に、暗い雲は不吉に見えました。

C1 verb /əbˈsɛs/

obsess

Meaning

To preoccupy or fill the mind of someone continually and to an excessive degree.

Example

She tends to obsess over small details.

C2 noun /əbˈstɛtrɪks/

obstetrics

産科

Meaning

The branch of medicine dealing with childbirth and care of women giving birth.

Example

She is studying obstetrics to become a specialist in childbirth.

彼女は産科を学んで、出産専門医になろうとしている。

B2 adverb /ˈoʊpənli/

Openly

率直に; 公然と

Meaning

in a frank and honest way; without concealment; publicly

Example

She spoke openly about her struggles with mental health.

彼女はメンタルヘルスの問題についてオープンに話した。

B2 noun /ˈɒt.ər/

Otter

カワウソ

Meaning

a mammal with webbed feet that lives near water and feeds on fish

Example

The playful otter swam gracefully in the river.

遊び好きなカワウソは川で優雅に泳いでいました。

A1 adjective /ˈɔːr.ɪndʒ/

Orange

オレンジ色

Meaning

having a color between red and yellow like that of a ripe orange fruit

Example

The orange sunset painted the sky magnificently.

オレンジ色の夕日は空を素晴らしく彩った。

C1 verb /aʊtˈwɪt/

outwit

巧妙に出し抜く

Meaning

to defeat or gain an advantage over someone by being more clever or cunning

Example

The fox managed to outwit the hunters.

キツネは猟師たちを出し抜くことができました。

C1 verb /ˌoʊvərˈpaʊər/

overpower

圧倒する

Meaning

To defeat or gain control over someone or something by using greater strength or force.

Example

The soldiers managed to overpower the enemy forces.

兵士たちは敵軍を圧倒することができました。

C2 adjective /ˈəʊ.dər.əs/

Odorous

芳香のある; 香り高い

Meaning

having a strong smell; fragrant; aromatic

Example

The garden was filled with odorous flowers.

庭は芳香のある花で満たされていた。

C1 noun /ˈɑn.set/

Onset

開始; 始まり

Meaning

the beginning or early stages of something; the start of a medical condition

Example

The onset of winter brought heavy snowfall.

冬の開始は大雪をもたらしました。

B2 noun /ˈɔːkɪstrə/

orchestra

オーケストラ

Meaning

a large group of musicians playing different instruments together

Example

The orchestra performed beautifully at the concert.

オーケストラはコンサートで素晴らしい演奏をしました。

C2 noun /ɔːˈreɪʃən/

oration

演説

Meaning

A formal speech, especially one given on a ceremonial occasion

Example

The president delivered an inspiring oration.

大統領は感動的な演説を行いました。

C1 adjective /ɔːˈneɪt/

ornate

華やかな

Meaning

elaborately or highly decorated

Example

The palace hall was filled with ornate furniture and paintings.

宮殿のホールは華やかな家具と絵画でいっぱいだった。

B2 adverb /ˈaʊtraɪt/

Outright

直接に; 完全に; ためらわずに

Meaning

completely; directly; without reservation or concealment

Example

She rejected the proposal outright.

彼女はその提案を直接拒否した。

C1 noun ˈaʊt.sɔːr.sɪŋ

outsourcing

アウトソーシング

Meaning

The practice of having certain job functions done outside a company instead of having an in-house department or employee handle them.

Example

Many companies use outsourcing to reduce labor costs.

多くの企業はコスト削減のためにアウトソーシングを利用しています。

B2 noun /ˈoʊvərpæs/

overpass

高架橋

Meaning

A bridge that carries one road or railway over another.

Example

The new overpass reduced traffic congestion in the city.

新しい高架橋は市内の交通渋滞を減らしました。

B1 adjective, adverb /ˈoʊvərɔːl/

overall

全体的に

Meaning

in general or as a whole

Example

Overall, the project has been successful.

全体的に、プロジェクトは成功しました。

B1 noun /ˌɑk.jəˈpeɪ.ʃən/

Occupation

職業; 仕事; 占領

Meaning

a job or profession; the action of taking control of a place

Example

Teaching is her chosen occupation.

教えることは彼女の選んだ職業です。

C2 noun /ˌɔːrəˈtɔːri.oʊ/

oratorio

宗教音楽作品

Meaning

A large-scale musical composition for orchestra, choir, and soloists, usually on a sacred theme, performed without costumes or scenery.

Example

Handel's 'Messiah' is one of the most famous oratorios ever written.

ヘンデルの『メサイア』は最も有名なオラトリオの1つです。

C1 adjective /ˈɒptɪk/

optic

視覚の

Meaning

Relating to the eye or vision.

Example

The optic nerve carries signals from the eye to the brain.

視神経は目から脳に信号を伝達します。

C1 adjective /ˌoʊvərˈbloʊn/

overblown

誇張された

Meaning

excessively exaggerated or inflated

Example

The controversy was overblown by the media.

メディアによって論争は誇張されました。

C2 adjective /ˈɑːbdjʊrət/

obdurate

頑固

Meaning

Stubbornly refusing to change one's opinion or course of action.

Example

He remained obdurate despite everyone's pleas.

彼は皆の懇願にもかかわらず、頑固なままでした。

B1 noun /ˌɒp.əˈtjuː.nə.ti/

opportunity

チャンス

Meaning

A favorable chance or set of circumstances that makes it possible to do something.

Example

She seized the opportunity to study abroad.

彼女は海外で勉強するチャンスをつかんだ。

C1 verb /ˌaʊtˈstrɛtʃ/

outstretch

外に伸ばす

Meaning

To extend or stretch something outward.

Example

He outstretched his hand to help her up.

彼は彼女を助けるために手を差し出した。

B2 adverb /ˈɒdli/

oddly

奇妙に

Meaning

in a strange or unusual way; unexpectedly

Example

Oddly, he didn’t seem upset by the bad news.

奇妙に、彼は悪い知らせにも動揺していなかった。

B2 noun /ɒpˈtɪʃən/

optician

眼鏡技師

Meaning

A person who makes or sells glasses and contact lenses.

Example

The optician adjusted my new glasses to fit better.

オプティシャンは私の新しい眼鏡をより良くフィットするように調整しました。

C2 noun /ˈɒbsɪkwi/

obsequy

葬儀

Meaning

A funeral rite, usually used in plural form obsequies.

Example

The village gathered for the obsequy of their beloved teacher.

村人たちは、愛する教師の葬儀のために集まりました。

C2 verb /ˌaʊtməˈnuːvər/

outmaneuver

巧妙に出し抜く

Meaning

to gain an advantage over an opponent by skillful or clever action

Example

The smaller company managed to outmaneuver its larger rival.

小さな会社は大きな競争相手を巧妙に出し抜くことに成功した。

B2 adjective /ˈɒnɡəʊɪŋ/

ongoing

進行中

Meaning

continuing; still in progress

Example

The ongoing project will finish next month.

進行中のプロジェクトは来月終了します。

C1 adjective /əˈbliːk/

Oblique

斜め; 対角線; 間接的または回避的

Meaning

slanting; diagonal; indirect or evasive

Example

The artist drew an oblique line across the canvas.

アーティストはキャンバスに斜めの線を描いた。

C1 adjective /ˈɔːrθədɑːks/

orthodox

Meaning

conforming to traditional beliefs or practices

Example

He comes from a very orthodox family.

C2 adjective /ˌoʊpəˈlɛsənt/

opalescent

オパール色の

Meaning

showing or reflecting a milky, iridescent light like an opal

Example

The opalescent sky glowed with shades of pink and blue.

オパレッセントな空はピンクと青の色合いで輝いていた。

C2 verb /oʊˈpaɪn/

opine

意見を述べる

Meaning

to express an opinion or belief

Example

The professor opined that the policy would fail.

教授はその政策が失敗するだろうと述べました。

B2 noun /ˌoʊ.vɚˈkraʊ.dɪŋ/

overcrowding

過密

Meaning

Excessive crowd or packed condition, having more people or vehicles in a place than the approved capacity.

Example

The subway system suffers from severe overcrowding during peak hours.

地下鉄システムはピーク時にひどい過密状態に苦しんでいます。

C1 verb /uːz/

ooze

にじみ出る

Meaning

to slowly flow or leak out through small openings or pores

Example

Blood began to ooze from the small cut.

血が小さな切り傷からにじみ出た。

C2 verb /əˈkluːd/

occlude

閉塞する

Meaning

To block or close up an opening or passage.

Example

The pipe was occluded by mineral deposits.

パイプは鉱物の堆積物で閉塞されていました。

B2 noun /ˌɑb.lɪˈɡeɪ.ʃən/

Obligation

義務

Meaning

a duty or commitment; something that must be done legally or morally

Example

Parents have an obligation to care for their children.

親は子供の世話をする義務がある。

C1 adjective ˈɒb.stɪ.nət

obstinate

頑固

Meaning

Refusing to change one's mind or accept others' advice easily.

Example

He remained obstinate despite the logical arguments.

彼は論理的な議論にもかかわらず頑固なままでいた。

C2 adjective /ˈoʊ.kən/

oaken

オーク材で作られた

Meaning

made of or resembling oak wood

Example

The villagers gathered around the oaken table in the hall.

村人たちはホールの中のオーク材のテーブルの周りに集まりました。

C1 adjective /ˈaʊt.kɑːst/

Outcast

社会的に排除された人

Meaning

rejected by society; excluded person

Example

He felt like an outcast in his new school.

彼は新しい学校でアウトキャストのように感じていた。

C1 adjective /ɒmˈnɪv.ər.əs/

Omnivorous

雑食性

Meaning

eating both plants and animals; feeding on various kinds of food

Example

Bears are omnivorous animals that eat both plants and meat.

クマは雑食性の動物で、植物と肉を食べます。

C1 adjective /oʊˈbiːs/

obese

肥満

Meaning

Extremely overweight; having an excessive amount of body fat.

Example

The doctor advised the obese patient to adopt a healthier lifestyle.

医者は肥満患者に健康的な生活様式を採用するように勧めました。

A2 noun /əˈlɪmpɪks/

olympics

オリンピック競技大会

Meaning

an international sports competition held every four years with athletes from many countries

Example

The Olympics bring athletes from all over the world together.

オリンピックは世界中のアスリートを一堂に集めます。

C2 adjective /ˌoʊdəˈrɪfərəs/

odoriferous

芳香のある

Meaning

having or giving off a smell, especially a strong or pleasant one

Example

The garden was filled with odoriferous flowers.

庭は芳香のある花でいっぱいでした。

B1 verb /əbˈzɜːrv/

observe

観察する

Meaning

to watch carefully; to notice or perceive something

Example

Scientists observe the behavior of animals in the wild.

科学者たちは野生動物の行動を観察します。

C1 adjective /ˌəʊ.vərˈɑː.tʃɪŋ/

overarching

全体的な, 包括的な, 包み込む

Meaning

Comprehensive or all-embracing; forming an arch over something.

Example

The overarching theme of the book is human resilience.

その本の大きなテーマは人間の回復力です。

C1 noun /ˈɔr.i.ənt/

Orient

東洋、特に東アジアの国々

Meaning

the East, especially countries of eastern Asia; to determine one's position or direction

Example

Many spices come from the Orient.

多くの香辛料がオリエントから来ています。

C1 noun /ˈaʊtˌkraɪ/

outcry

抗議

Meaning

A strong expression of public anger or disapproval.

Example

The decision sparked an outcry among the citizens.

その決定は市民の間で抗議を引き起こしました。

C2 adjective /ɒˈstɛnsɪv/

ostensive

明示的

Meaning

clearly demonstrative or pointing out; explicitly shown

Example

The teacher gave an ostensive example to clarify the concept.

先生はその概念を明確にするために、明示的な例を示しました。

A2 adjective /ˈɑp.ə.zɪt/

Opposite

反対の; 完全に異なる; 向かい合っている; 逆の;

Meaning

Contrary; completely different; facing each other; reverse;

Example

They have opposite views on politics but remain good friends.

彼らは政治に関して対立した見解を持っていますが、良い友達のままです。

B2 noun /əˈpoʊ.nənt/

Opponent

対戦相手; ライバル

Meaning

a person who disagrees with or resists a proposal or practice; someone who competes against another

Example

The chess player defeated his strongest opponent.

チェスのプレーヤーは最強の対戦相手を倒した。

B2 noun, verb /ˈaʊtlɔː/

outlaw

Meaning

as a noun: a person who breaks the law and lives outside its protection; as a verb: to make something illegal

Example

The government decided to outlaw the harmful practice.

C1 adjective /ˌɔːrnəˈmɛntl/

ornamental

装飾的な

Meaning

Serving as decoration; decorative rather than functional.

Example

The garden was filled with ornamental plants.

庭は装飾的な植物でいっぱいだった。

C1 noun /əˈfen.dər/

Offender

犯罪者; 法律違反者

Meaning

a person who commits an illegal act; someone who breaks the law

Example

The young offender was sentenced to community service.

その若い犯罪者はコミュニティサービスを命じられました。

B2 adjective /ˈɔɪl.i/

Oily

油っぽい; 油で覆われた; 脂っこい

Meaning

covered with oil; containing oil; greasy

Example

Her oily skin needs special care.

彼女の油っぽい肌は特別なケアが必要です。

A2 pronoun /aʊərˈsɛlvz/

ourselves

私たち自身

Meaning

used by the speaker to refer to themselves and one or more others as the object of the verb

Example

We should help ourselves before helping others.

私たちは他の人を助ける前に、自分たち自身を助けるべきです。

B2 verb /ˈɒkjʊpaɪ/

occupy

占める / 占有する / 居住する

Meaning

to take up space or time; to live or work in a place

Example

The new family will occupy the house next month.

新しい家族は来月その家に入居する予定です。

B2 noun /ˈaʊt.breɪk/

Out-break

発生

Meaning

a sudden occurrence or eruption of something, especially disease or violence

Example

The outbreak of flu affected many students in the school.

インフルエンザの流行は学校の多くの生徒に影響を与えた。

C1 adjective /oʊˈvɜːrt/

overt

公然

Meaning

Done or shown openly; not hidden or secret.

Example

There was an overt display of hostility between the rivals.

ライバルの間に公然とした敵意の表れがあった。

B2 verb /ɒpt/

opt

選ぶ

Meaning

to choose or decide to do something instead of something else

Example

Many students opt to study abroad for better opportunities.

多くの学生がより良い機会のために海外で学ぶことを選択します。

C2 noun /ˈɔːrdnəns/

ordnance

軍需品

Meaning

Military supplies including weapons, ammunition, and combat equipment.

Example

The army stored ordnance in a secure facility outside the city.

軍隊は都市外の安全な施設に軍需品を保管していた。

C1 adjective /ˌɔːrθəˈpiːdɪk/

orthopedic

骨や筋肉の変形の修正に関連する

Meaning

Relating to the correction of deformities of bones or muscles.

Example

She visited an orthopedic surgeon for her back pain.

彼女は背中の痛みのために整形外科医に行った。

B2 noun /ˈɒs.trɪtʃ/

Ostrich

ダチョウ

Meaning

a large flightless bird native to Africa with long legs and neck

Example

The ostrich is the world's largest bird.

ダチョウは世界最大の鳥です。

A1 adverb /wʌns/

Once

一度; 過去に

Meaning

one time only; at some time in the past; formerly

Example

I have been to Paris once in my life.

私は一度だけパリに行ったことがあります。

C2 noun /ɔːrˈθɑːɡrəfi/

orthography

正書法

Meaning

The conventional spelling system of a language.

Example

English orthography can be confusing for learners.

英語の正書法は学習者にとって混乱を招くことがあります。

B2 noun/verb /ˌoʊvərˈlæp/

overlap

Meaning

To extend over and cover partly; an area where things coincide.

Example

The two meetings overlap by an hour.

C2 noun /ˈoʊ.kəm/

oakum

古いロープの繊維

Meaning

loose fibers obtained by untwisting old ropes, used for caulking ships

Example

The shipbuilders used oakum to seal the gaps in the wooden planks.

船大工たちは木の板の隙間を塞ぐためにオーカムを使いました。

C1 noun /ˌɒk.sɪ.dʒɪˈneɪ.ʃən/

oxygenation

酸素供給または治療

Meaning

The process of supplying or treating with oxygen.

Example

Deep breathing exercises improve oxygenation of the body.

深呼吸の練習は身体の酸素供給を改善します。

B1 adjective /əˈrɪdʒ.ɪ.nəl/

Original

元の; 基本的な; 本物の

Meaning

first; fundamental; primary; authentic

Example

This is the original document, not a copy.

これはオリジナルの文書で、コピーではありません。

C2 verb /ˌoʊvərˈliːp/

overleap

飛び越える

Meaning

To jump over something; to omit or disregard something.

Example

He managed to overleap the fence easily.

彼は簡単にフェンスを飛び越えました。

C1 adjective /əbˈdʒek.ʃən.ə.bəl/

Objectionable

不快な

Meaning

arousing distaste or opposition; unpleasant or offensive

Example

His objectionable behavior made everyone uncomfortable.

彼の不快な行動は、皆を不快にさせた。

C2 adjective /ˌɔːfˈkiː/

off-key

外れた音

Meaning

out of tune; not in accordance with expected standards

Example

The singer was slightly off-key during the performance.

歌手はパフォーマンス中に少し外れた音だった。

B2 noun /ˈaʊtˌsɛt/

outset

開始

Meaning

the beginning or start of something

Example

From the outset, the project seemed ambitious but achievable.

最初から、プロジェクトは野心的だが達成可能に見えました。

A1 adjective /oʊld/

old

古い

Meaning

having lived for a long time; not new or young

Example

He still drives his old car.

彼は今でも古い車を運転しています。

C1 verb /ˈɒp.tɪ.maɪz/

optimize

最適化する

Meaning

To make the best or most effective use of a situation, opportunity, or resource.

Example

The company is working to optimize its supply chain.

会社はサプライチェーンの最適化に取り組んでいます。

C2 noun /ɑːlˈfækʃən/

olfaction

嗅覚

Meaning

The sense of smell; the process of detecting and perceiving odors.

Example

Dogs have a highly developed sense of olfaction.

犬は非常に発達した嗅覚を持っています。

C1 verb /ˈoʊvərˌhɔːl/

overhaul

完全な改修

Meaning

to examine thoroughly and repair or improve something that is worn or ineffective

Example

The company decided to overhaul its outdated computer system.

会社は古くなったコンピュータシステムのオーバーホールを決定した。

B2 noun /ˈɔr.fən/

Orphan

孤児

Meaning

a child whose parents are dead; someone without protective support

Example

The orphan was adopted by a loving family.

その孤児は愛情深い家族に養子として迎えられました。

C1 adjective /ˈəʊnərəs/

onerous

重い

Meaning

involving a great deal of effort, difficulty, or burden

Example

Fulfilling the contract proved to be an onerous task for the company.

契約を履行することは会社にとって負担の大きい仕事だと証明された。

C2 noun /ˈoʊdiəm/

odium

嫌悪

Meaning

general or widespread hatred or disgust directed toward someone as a result of their actions

Example

The scandal brought public odium on the corrupt minister.

スキャンダルは腐敗した大臣に対する公衆の嫌悪を引き起こした。

C2 noun /oʊd/

ode

オード

Meaning

a lyrical poem, often expressing praise or strong emotions

Example

The poet wrote an ode to the beauty of nature.

詩人は自然の美に対するオードを書いた。

C2 noun /ˈɒn.rʌʃ/

onrush

突発的な流れ

Meaning

A sudden powerful forward or downward rush or flow.

Example

The onrush of water swept away the bridge.

水の突発的な流れが橋を流しました。

B1 verb /ˈɔːrɡənaɪz/

organize

整理する

Meaning

to arrange systematically; to plan and coordinate

Example

She organized a surprise party for her friend.

彼女は友達のためにサプライズパーティーを企画した。

C1 noun /ˈɑːlɪˌɡɑːrki/

oligarchy

寡頭政治

Meaning

A small group of people having control of a country, organization, or institution.

Example

The nation was ruled by a wealthy oligarchy that controlled all resources.

その国は裕福なオリガーキーによって支配され、すべての資源を支配していました。

C1 adjective /əˈblaɪdʒɪŋ/

obliging

親切な

Meaning

Willing to help or do favors; accommodating.

Example

The staff at the hotel were very obliging and friendly.

ホテルのスタッフはとても親切で友好的でした。

C1 noun ˌɒb.səˈlɛs.əns

obsolescence

陳腐化

Meaning

The process of becoming obsolete or outdated and no longer used.

Example

The rapid advancement of technology leads to the obsolescence of old devices.

テクノロジーの急速な進歩は古いデバイスの陳腐化を引き起こします。

C2 noun /ˈɒrɪz(ə)n/

orison

祈り

Meaning

a prayer, especially a devout or formal one

Example

He whispered a quiet orison before going to sleep.

寝る前に静かな祈りをささやいた。

C2 adjective /ˈɔːrəˌtʌnd/

orotund

豊かで明確な声

Meaning

full, rich, and clear in sound; pompous in style

Example

The actor's orotund voice filled the theater.

俳優の豊かな声が劇場に響き渡った。

A1 adjective /əʊˈkeɪ/

okay

大丈夫

Meaning

used to express agreement or acceptance

Example

It's okay to leave early today.

今日は早く帰るのは大丈夫です。

B2 noun/verb /ˈoʊvərˌdoʊs/

overdose

過剰摂取

Meaning

An excessive and dangerous amount of a drug; to take too much of a substance.

Example

He was rushed to the hospital after a drug overdose.

薬物の過剰摂取で病院に運ばれました。

B2 adjective, verb /əbˈskjʊr/

obscure

不明確

Meaning

Not clearly expressed or understood; to make something difficult to see or understand.

Example

The meaning of the poem was obscure to most readers.

詩の意味はほとんどの読者には不明確でした。

B2 verb əbˈzɜːrvd

observed

祝う

Meaning

To celebrate or keep a religious or other festival.

Example

The day is observed annually to raise awareness.

その日は毎年意識を高めるために祝われます。

C1 adjective /əbˈzɜːrvənt/

Observant

観察力のある

Meaning

quick to notice things; watchful; attentive

Example

The observant detective noticed every small detail at the crime scene.

観察力のある探偵は犯罪現場のあらゆる小さな詳細に気づきました。

C2 noun /ˌɑːbdʒərˈɡeɪʃən/

objurgation

厳しい叱責

Meaning

a harsh scolding or strong rebuke

Example

His misconduct earned him a severe objurgation from the manager.

彼の不正行為はマネージャーから厳しい叱責を受けた。

C1 noun ˌɒk.sɪˈdeɪ.ʃən

oxidation

酸化

Meaning

A chemical reaction that involves the combination of a substance with oxygen, often causing deterioration.

Example

Oxidation causes metal surfaces to weaken.

酸化は金属表面を弱めます。

B2 verb /ˌoʊvərˈsiː/

oversee

監督する

Meaning

to supervise or watch over something; to manage and direct

Example

The manager will oversee the entire construction project.

マネージャーは全体の建設プロジェクトを監督します。

B2 noun /əˈfens/

Offence

違反; 犯罪

Meaning

a breach of law or rule; an annoyance or resentment

Example

Stealing is a serious offence punishable by law.

窃盗は法律で罰せられる重大な違反です。

C1 noun /ˈɑd.ɪ.ti/

Oddity

珍奇な現象

Meaning

something that is strange or unusual; a peculiar trait

Example

His habit of sleeping standing up was considered an oddity.

彼の立って寝る習慣は珍奇な現象と見なされていました。

C2 noun /əˈprəʊ.bri.əm/

opprobrium

非難, 恥辱

Meaning

Harsh criticism or public disgrace.

Example

The scandal brought opprobrium on the politician.

スキャンダルは政治家に非難を浴びせた。

B2 verb /əˈpoʊz/

oppose

反対する

Meaning

to disagree with or resist; to act against

Example

Many citizens oppose the new tax policy.

多くの市民が新しい税制政策に反対しています。

C1 noun /ˌɒbstəˈtrɪʃən/

obstetrician

産科医

Meaning

A doctor specializing in pregnancy, childbirth, and women's reproductive health.

Example

The obstetrician monitored the mother’s health throughout the pregnancy.

産科医は妊娠中の母親の健康を監視しました。

B2 verb /ˌoʊvərˈteɪk/

overtake

追い越す

Meaning

to catch up with and pass someone or something; to surpass

Example

The runner managed to overtake his competitor in the final lap.

ランナーは最後の周回で競争相手を追い越しました。