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。

A2 adjective/adverb /ˈɒnˌlaɪn/

online

オンライン

Meaning

connected to or available through the internet

Example

I prefer shopping online rather than going to stores.

私はお店に行くよりもオンラインで買い物をする方が好きです。

B2 noun /əbˈsɛʃən/

obsession

執着

Meaning

An idea, thought, or concern that continually preoccupies or intrudes on a person's mind.

Example

His obsession with success drove him to work day and night.

成功への執着が彼を昼夜働かせた。

A2 noun /ˈɔr.dər/

Order

命令; 順序

Meaning

a command or instruction; the arrangement of things following a particular sequence

Example

The teacher gave an order to sit down quietly.

教師は静かに座るよう命じました。

A2 noun /ˈɒm.lət/

Omelet

オムレツ

Meaning

a dish made from beaten eggs cooked in a frying pan and often folded around a filling

Example

She made a cheese omelet for breakfast.

彼女は朝食にチーズオムレツを作った。

B1 adjective /əˈkeɪ.ʒən.əl/

Occasional

偶然の

Meaning

occurring infrequently or irregularly; happening from time to time

Example

She enjoys occasional walks in the park.

彼女は公園で偶然の散歩を楽しんでいます。

C1 noun /oʊˈbɪt.ʃu.er.i/

Obituary

訃報

Meaning

a notice of someone's death published in a newspaper; biographical account of deceased person

Example

The newspaper published his obituary yesterday.

新聞は昨日彼の訃報を掲載しました。

C2 noun /ˌɔːrdɪˈneɪʃən/

ordination

任命式

Meaning

The ceremony of conferring holy orders or official religious authority.

Example

The church held a special service for the ordination of new priests.

教会は新しい神父の任命のために特別なサービスを行いました。

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 noun /əbˈdʒɛktər/

objector

反対者

Meaning

a person who expresses opposition or disapproval to something

Example

The objector raised his concerns during the town meeting.

反対者は市議会の会議中に自分の懸念を表明しました。

B2 noun /əbˈdʒek.ʃən/

Objection

異議; 反対; 抗議;

Meaning

an expression of disagreement or disapproval; a reason for disagreeing

Example

The lawyer raised an objection during the trial.

弁護士は裁判中に異議を唱えました。

C2 adjective /əbˈstrɛpərəs/

obstreperous

騒がしくて制御が難しい

Meaning

Noisy and difficult to control.

Example

The obstreperous students disrupted the class.

騒がしい学生たちが授業を妨害した。

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。

C2 noun /ˈɔːrɪndʒfɪn ˈleɪbiːoʊ/

Orangefin labeo

オレンジフィンラベオ

Meaning

a freshwater fish species native to South Asian rivers, commonly found in Bangladesh and India

Example

The orangefin labeo is an important food fish in Bangladesh.

オレンジフィンラベオはバングラデシュで重要な食用魚です。

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。

B2 verb /əˈrɪdʒɪneɪt/

originate

起源する

Meaning

to come into existence; to begin; to create or produce

Example

The tradition originated in ancient times.

その伝統は古代の時代に起源を持っています。

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。

A1 noun /ɒkˈtoʊbər/

october

10月

Meaning

the tenth month of the year in the Gregorian calendar

Example

The weather becomes cooler in October.

10月になると天気が涼しくなります。

C2 noun ˈoʊʃən ˌstrætɪfɪˈkeɪʃən

ocean stratification

海洋の成層

Meaning

The formation of layers in ocean water due to differences in density.

Example

Ocean stratification affects marine biodiversity.

オーシャンストラティフィケーションは海洋生物多様性に影響を与えます。

C1 noun /əbˈzɜːrvətɔːri/

observatory

天文台

Meaning

A building equipped for observing astronomical or meteorological events.

Example

The observatory is open to the public on weekends.

天文台は週末に一般公開されています。

C2 noun /ˌɒn.əˌmæt.əˈpiː.ə/

onomatopoeia

オノマトペ

Meaning

The formation of a word from a sound associated with what is named.

Example

The word 'buzz' is an example of onomatopoeia.

'バズ'という言葉はオノマトペの一例です。

C1 adjective /əbˈtjuːs/

Obtuse

鈍い; 理解が遅い; 愚か

Meaning

annoyingly insensitive or slow to understand; lacking in intelligence or perception

Example

He was being deliberately obtuse about the instructions.

彼は指示に関して意図的に鈍かった。

C1 adjective /ˌoʊvərˈbɛrɪŋ/

overbearing

押しつけがましい

Meaning

unpleasantly or arrogantly domineering

Example

His overbearing attitude made everyone uncomfortable.

彼の押しつけがましい態度は、みんなを不快にさせた。

B2 noun /ɔːˈræŋ.ʊˌtæŋ/

Orang-Outang

オランウータン

Meaning

a large arboreal ape with long reddish hair, long arms, and hooked hands and feet, native to Borneo and Sumatra

Example

The orangutan swings gracefully through the forest canopy.

オランウータンは森の樹冠を優雅に渡ります。

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。

B2 noun /ˈɔːɡən/

organ

臓器

Meaning

a part of the body that performs a specific function

Example

The heart is an important organ in the human body.

心臓は人間の体の重要な臓器です。

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。

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。

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。

B1 noun ˌɔː.ɡən.aɪˈzeɪ.ʃənz

organizations

組織

Meaning

Organized groups of people with a particular purpose

Example

Organizations play a key role in policymaking.

組織は政策形成において重要な役割を果たします。

B2 noun /oʊˈbiː.di.əns/

Obedience

服従

Meaning

compliance with an order, request, or law; submission to authority

Example

Children should show obedience to their parents.

子供たちは両親に従うべきです。

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。

A1 adjective /oʊˈkeɪ/

ok

わかった

Meaning

used to indicate agreement, approval, or understanding

Example

Okay, let's go to the park.

わかった、じゃあ公園に行こう。

C2 adjective /ˌɒbsəˈlɛsnt/

obsolescent

時代遅れの

Meaning

Becoming outdated or on the way to becoming obsolete.

Example

The obsolescent technology could not compete with modern devices.

時代遅れの技術は現代のデバイスには競争できなかった。

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。

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 /ˌoʊvərˈlʊk/

overlook

見落とす

Meaning

to fail to notice or consider something; to have a view from above

Example

It's easy to overlook small details when you're in a hurry.

急いでいると、細かい点を見落とすことがあります。

C2 verb /ˈɒsɪfaɪ/

ossify

骨化する

Meaning

to turn into bone or become rigid and inflexible

Example

With age, some tissues tend to ossify.

年を重ねると、一部の組織が骨化する傾向があります。

C2 noun /oʊf/

Oaf

不器用で愚かな、無神経な人

Meaning

a clumsy, stupid, or insensitive person

Example

Don't be such an oaf - handle the dishes carefully!

そんなオーフにならないで – お皿は気をつけて洗って！

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。

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 /ˈɔːɡənɪzəm/

organism

生物

Meaning

a living thing that has an organized structure and can grow and reproduce

Example

Every organism needs water to survive.

すべての生物は生き残るために水を必要とします。

C1 noun /ˈoʊ.vər spɪl/

Over-spill

オーバーフロー

Meaning

the overflow of liquid from a container; excess that cannot be contained

Example

The overspill from the river flooded nearby farms.

川の溢れが近くの農場を水浸しにした。

B1 adjective /ˌoʊvərˈweɪt/

overweight

過体重

Meaning

heavier than is considered healthy or normal

Example

The doctor advised him to lose weight as he was overweight.

医者は体重を減らすようにアドバイスしました、なぜなら彼は過体重だったからです。

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。

C1 adjective /ˌaʊtˈspoʊkən/

Outspoken

率直

Meaning

frank; speaking directly

Example

She is known for being outspoken about social issues.

彼女は社会問題について率直に話すことで知られています。

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。

C1 noun /ˈɔːrdɪnəns/

ordinance

条例

Meaning

An authoritative rule, law, or decree issued by a city, town, or authority.

Example

The city council passed an ordinance banning smoking in public parks.

市議会は公共公園での喫煙を禁じる条例を可決しました。

C1 verb /ˈɔːstrəˌsaɪz/

ostracize

追放する

Meaning

to exclude someone from a group or society; to banish or shun

Example

After the scandal, he was ostracized by his former colleagues.

スキャンダル後、彼は元同僚に追放された。

C2 adjective /ˈoʊ.pən ˈhæn.dɪd/

Open-handed

寛大な; 自由な

Meaning

Generous; liberal; giving freely;

Example

He is very open-handed with his money and always helps those in need.

彼は自分の金に非常に寛大で、いつも困っている人々を助けています。

C2 verb /əbˈvɜːrt/

obvert

反転する

Meaning

To turn something so as to face in a different direction; in logic, to convert a proposition by negating both subject and predicate.

Example

The teacher asked the students to obvert the statement for practice.

先生は生徒たちに練習のためにその声明をオブバートするように頼みました。

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。

C1 adjective /aʊtˈmoʊdɪd/

outmoded

時代遅れ

Meaning

No longer in fashion or useful; outdated.

Example

That old computer is completely outmoded.

その古いコンピューターは完全に時代遅れです。

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。

C2 adjective /ˈoʊdiəs/

odious

忌まわしい

Meaning

extremely unpleasant or repulsive

Example

The dictator was remembered for his odious crimes.

その独裁者は彼の忌まわしい犯罪で記憶されました。

B2 adjective ˌɒp.ərˈeɪ.ʃən.əl

operational

運用可能

Meaning

In working order; ready for use.

Example

The space project will be operational by 2025.

宇宙計画は2025年までに運用可能になります。

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。

A1 pronoun /ˈʌðərz/

others

他の人々

Meaning

people or things distinct from the ones already mentioned or known

Example

I like to spend time with others.

私は他の人々と時間を過ごすのが好きです。

C1 adjective /ˈɑp.ər.ə.tɪv/

Operative

作動中の; 効力を持つ; 仕事をしている; 操作可能な;

Meaning

Functioning; in effect; working; active;

Example

The new safety protocols became operative immediately after the accident.

新しい安全プロトコルは事故後すぐに作動しました。

C1 verb /ˌoʊvərˈθroʊ/

overthrow

幸せ

Meaning

To remove a leader or government from power, often by force.

Example

The rebels planned to overthrow the corrupt regime.

彼女は賞を受け取ったとき、幸せを隠すことができなかった。

C1 noun /ˈɒptɪks/

optics

光学

Meaning

The branch of physics dealing with light and vision.

Example

She studied optics to understand how lenses work.

彼女はレンズがどのように機能するかを理解するために光学を学びました。

C2 noun /ˈɔːrdʒi/

orgy

乱行

Meaning

A wild party involving excessive indulgence, especially of a sexual nature.

Example

The novel described a scandalous orgy in a wealthy mansion.

その小説は、裕福な邸宅でのスキャンダラスな乱行を描いています。

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。

C2 noun ˈɒpjʊləns

opulence

富裕

Meaning

Great wealth or luxuriousness.

Example

The opulence of the mansion was evident in its ornate furnishings.

豪邸の富裕さはその華やかな家具に明らかでした。

C1 noun /ˈɔːrθədɑːksi/

orthodoxy

正統

Meaning

traditional or generally accepted beliefs and practices

Example

The religious leader defended the orthodoxy of the faith.

宗教指導者は信仰の正統性を守った。

C1 noun /ˌɑːk.sɪˈmɔːr.ɒn/

oxymoron

オキシモロン

Meaning

a figure of speech where two contradictory terms are combined

Example

The phrase 'deafening silence' is a classic oxymoron.

「耳をつんざくような静けさ」というフレーズは、典型的なオキシモロンです。

B1 verb /ˈɒpəreɪtɪŋ/

operating

運営する

Meaning

to control or manage the functioning of something

Example

The company has been operating in this market for five years.

その会社はこの市場で5年間運営されています。

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。

B2 noun /ˈaʊt.kʌm/

Outcome

結果; 結末;

Meaning

the result or consequence of an action or situation; the final product

Example

The outcome of the election surprised everyone.

選挙の結果は皆を驚かせました。

A1 verb /ˈoʊpən/

open

開ける

Meaning

to move something so as to allow access; to begin

Example

Please open the door for me.

ドアを開けてください。

B1 adjective /ˈaʊtər/

outer

外部

Meaning

situated on or toward the outside; external

Example

The outer layer of the jacket is waterproof.

ジャケットの外側の層は防水です。

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。

B1 adjective /ˌoʊvərˈsiːz/

overseas

海外

Meaning

in or to a foreign country across the sea

Example

He went overseas for higher education.

彼は高等教育のために海外に行った。

C2 noun /ɒmˈnɪʃəns/

omniscience

全知

Meaning

the state of knowing everything

Example

The novel's narrator has an air of omniscience, revealing every character's thoughts.

小説の語り手は全知の空気をまとい、すべてのキャラクターの考えを明らかにしている。

C2 adjective /ˈoʊ.pən ˈhɑrt.ɪd/

Open-hearted

オープンハート; 寛大で誠実; 心温かく受け入れる;

Meaning

Kind and generous; sincere and honest; warmly receptive;

Example

She welcomed the strangers with an open-hearted smile and invited them for dinner.

彼女は見知らぬ人々を心温かい笑顔で迎え、夕食に招待した。

C1 verb /aʊtˈlɪv/

outlive

より長生きする

Meaning

to live longer than someone or something else

Example

She outlived all her siblings.

彼女はすべての兄弟姉妹より長生きしました。

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 /ˈɒkjʊlər/

ocular

眼科の

Meaning

Relating to the eye or vision.

Example

The patient was referred to a specialist for ocular treatment.

患者は眼科専門医に紹介されました。

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。

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。

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。

A2 noun /ˈɒbdʒɪkt/

object

物体

Meaning

a thing that can be seen and touched

Example

The table is an object in the room.

テーブルは部屋の中の物体です。

C1 adjective /ˌɒmnɪˈprezənt/

omnipresent

至る所に存在する

Meaning

(of God) present everywhere at the same time.

Example

Social media has become an omnipresent force in modern society.

ソーシャルメディアは現代社会において至る所に存在する力となりました。

A1 pronoun /aʊər/

our

私たちの

Meaning

belonging to or associated with the speaker and one or more other people

Example

This is our house.

これは私たちの家です。

B2 noun ˈəʊ.və.hed

overhead

間接費

Meaning

Ongoing business expenses not directly attributable to creating a product or service.

Example

The company reduced its overhead to increase profits.

会社は利益を増やすために間接費を削減した。

B2 adjective ɔːrˈɡæn.ɪk

organic

有機

Meaning

Produced or involving production without the use of chemical fertilizers, pesticides, or other artificial agents.

Example

Organic farming improves soil health and reduces pollution.

有機農業は土壌の健康を改善し、汚染を減少させます。

A2 noun /ˈɒf.ɪs/

office

オフィス

Meaning

a room or building where people work, usually at desks

Example

She left the office early to attend a family event.

彼女は家族のイベントに出席するために早くオフィスを出ました。

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。

C2 noun /ˈɒkjʊlɪst/

oculist

眼科医

Meaning

An old-fashioned term for an eye doctor or ophthalmologist.

Example

The village oculist was known for treating various eye diseases.

村のオキュリストは、さまざまな目の病気を治療することで知られていました。

C2 verb /ˌoʊvərˈstraɪd/

overstride

大きな一歩で越える

Meaning

To stride over something; to step across with long steps.

Example

He managed to overstride the narrow stream with ease.

彼は狭い小川を簡単に越えることができました。

B2 adjective /ˌoʊvərˈwɛlmɪŋ/

overwhelming

圧倒的

Meaning

Very intense; overpowering.

Example

Large tasks can feel overwhelming.

大きな仕事は圧倒的に感じることがあります。

C2 verb /ˈɑːbdʒərˌɡeɪt/

objurgate

厳しく叱る

Meaning

to scold or rebuke severely

Example

The teacher objurgated the student for being dishonest.

先生は不正直な生徒を厳しく叱った。

A1 interjection /oʊ/

oh

オー

Meaning

used to express surprise, realization, or understanding

Example

Oh, I didn't know you were here!

オー、あなたがここにいるとは思わなかった！

C1 adjective /əˈblɪɡ.ə.tɔː.ri/

obligatory

義務的

Meaning

Required by a legal, moral, or other rule; compulsory.

Example

Wearing a seatbelt is obligatory in most countries.

ほとんどの国でシートベルトを着用することは義務です。

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。

B2 noun /ˈɔr.fən.ɪʒ/

Orphanage

孤児院

Meaning

an institution for the care and education of children who have lost their parents

Example

The charity built a new orphanage for homeless children.

チャリティーはホームレスの子供たちのために新しい孤児院を建てました。

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。

B2 adverb /əˈfɪʃəli/

officially

公式に

Meaning

in a formal or authorized way

Example

The building was officially opened by the mayor.

その建物は市長によって公式に開かれました。

C2 noun /ˈɒbsɪkwiːz/

obsequies

葬儀儀式

Meaning

Funeral rites or ceremonies.

Example

The obsequies for the late leader drew thousands of mourners.

故リーダーの葬儀儀式には、数千人の弔問客が集まりました。

A1 preposition /ʌv/

of

の

Meaning

expressing the relationship between a part and a whole

Example

The book is on the table, in front of the window.

本はテーブルの上にあり、窓の前にあります。

目標

Meaning

A thing aimed at or sought; a goal.

Example

The main objective is to test sustainability.

メインオブジェクティブは持続可能性をテストすることです。