occident
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C2 noun /ˈɒksɪdənt/

occident

西洋
Meaning
The countries of the West, especially Europe and America.
Example
The Occident has a long history of philosophical thought.
西洋には長い哲学的思考の歴史があります。
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。
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！
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 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。
C2 noun /oʊliˈændər/

Oleander

オレアンダー
Meaning
a poisonous evergreen shrub with clusters of white, pink, or red flowers
Example
The beautiful oleander flowers bloomed in the garden despite their toxic nature.
美しいオレアンダーの花が庭で咲いていましたが、その毒性に関わらず。
B1 adverb /əˈrɪdʒɪnəli/

originally

元々
Meaning
in the beginning, at first
Example
Originally, she wanted to be a doctor.
元々、彼女は医者になりたかった。
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。
B2 verb /ˌoʊvərˈduː/

overdo

やりすぎる
Meaning
to do something too much; to exaggerate or carry to excess
Example
Don't overdo the exercise on your first day at the gym.
初日はジムで運動をやりすぎないでください。
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 noun ˌoʊ.vɚˈɡreɪ.zɪŋ

overgrazing

過剰放牧
Meaning
The practice of allowing livestock to graze to the point of damaging vegetation.
Example
Overgrazing leads to soil erosion and loss of biodiversity.
過剰放牧は土壌の浸食と生物多様性の喪失を引き起こします。
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。
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。
B2 noun /əbˈzɜːvər/

observer

観察者
Meaning
a person who watches or notices something
Example
The observer took notes during the meeting.
観察者は会議中にメモを取った。
B2 noun ˈɒksɪdʒən prəˈdʌkʃən

oxygen production

酸素生産
Meaning
The process of generating oxygen through photosynthesis or other means.
Example
Plants are vital for oxygen production and the maintenance of life.
植物は酸素の生産と生命の維持に不可欠です。
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。
C1 adjective /ˌaʊt əv ðə ˈweɪ/

out-of-the-way

人里離れた場所
Meaning
remote or unusual; not in a convenient or usual location
Example
They stayed in an out-of-the-way village.
彼らは人里離れた村に滞在しました。
C1 noun /ˈoʊvərˌtoʊn/

overtone

微妙な意味
Meaning
A subtle quality, implication, or additional meaning beyond the obvious.
Example
His speech had political overtones that were hard to ignore.
彼のスピーチには無視できない政治的なニュアンスが含まれていました。
B2 noun /ˌɒpəˈzɪʃən/

opposition

反対
Meaning
the action of opposing or resisting something
Example
The opposition to the new law was strong.
新しい法律に対する反対は強かった。
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。
C1 verb ˈɔː.kɪ.streɪ.tɪd

orchestrated

精巧に組織された
Meaning
Planned or coordinated carefully and deliberately.
Example
The attacks were orchestrated with precision.
攻撃は正確に組織されていた。
B1 adverb /əˈkeɪʒənəli/

Occasionally

時々; たまに;
Meaning
sometimes; from time to time; not regularly
Example
I occasionally visit my grandmother on weekends.
私は時々週末に祖母を訪ねます。
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。
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。
C1 adjective /ɒˈstɛnsəbl/

ostensible

見せかけの
Meaning
stated or appearing to be true, but not necessarily so
Example
His ostensible reason for leaving was illness, but many doubted it.
彼の出発の見せかけの理由は病気だったが、多くの人がそれを疑っていた。
B2 noun /ˈaʊtskɜːrts/

outskirts

都市の郊外
Meaning
The outer parts of a town or city, away from the center.
Example
They moved to the outskirts of the city for a quieter life.
彼らは静かな生活を求めて都市の郊外に引っ越しました。
A1 verb, adjective /oʊn/

own

所有する
Meaning
to possess something; belonging to oneself
Example
She owns a beautiful house in the city.
彼女は市内に美しい家を持っています。
B2 noun /ˌɑb.zɚˈveɪ.ʃən/

Observation

観察
Meaning
the action of watching something carefully; a comment or remark
Example
The scientist made careful observations of the experiment.
科学者は実験を慎重に観察しました。
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。
A2 adjective /ˈɒb.vi.əs/

Obvious

明白な; 簡単に理解できる
Meaning
easily perceived or understood; clear and apparent to the mind
Example
It was obvious that she was upset about something.
それは彼女が何かについて不満を抱えていることが明らかでした。
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 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。
C1 adjective /ˌɑːpərˈtuːn/

opportune

適切な瞬間
Meaning
Happening at a suitable or convenient time.
Example
She arrived at an opportune moment to help.
彼女は助けるために適切な瞬間に到着しました。
C2 noun /ˈoʊ.vər.let/

Overlet

ベッドパッド
Meaning
a thin mattress or pad placed over a bed for additional comfort
Example
The overlet makes the bed more comfortable to sleep on.
オーバーレットはベッドをより快適にして眠りやすくします。
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 /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。
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 /ˈɒptɪməm/

optimum

最適
Meaning
Most conducive to a favorable outcome; best.
Example
To achieve optimum results, we need to improve efficiency.
最適な結果を得るためには、効率を改善する必要があります。
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 verb /əbˈstrʌkt/

obstruct

妨げる
Meaning
to block or hinder progress; to prevent or impede movement
Example
The fallen tree obstructed the road for several hours.
倒れた木が数時間道路をふさぎました。
A1 preposition /ɒn/

on

上
Meaning
physically in contact with and supported by a surface
Example
The book is on the table.
本はテーブルの上にあります。
C1 noun /ˈoʊ.mən/

Omen

未来の良いまたは悪い運命の兆し
Meaning
an event regarded as a sign of future good or bad luck
Example
Many people consider a black cat crossing your path a bad omen.
多くの人々は、黒猫が道を横切ることを悪いオーメンだと考えています。
B1 noun /əˈpɪn.jən/

Opinion

意見
Meaning
a view or judgment formed about something; a belief or assessment based on grounds short of proof
Example
In my opinion, this is the best solution.
私の意見では、これは最良の解決策です。
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。
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。
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。
C1 noun /əˈpreʃ.ən/

Oppression

抑圧; 虐待; 圧政;
Meaning
cruel or unjust treatment or exercise of authority; the state of being subject to harsh treatment
Example
The people fought against political oppression.
人々は政治的な抑圧に反対して戦った。
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。
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。
C2 noun /ˈɑb.lə.kwi/

Obloquy

厳しい批判または言葉による虐待; 公共の非難
Meaning
harsh criticism or verbal abuse; strong public condemnation
Example
The politician faced obloquy after the scandal.
政治家はスキャンダルの後、厳しい批判を受けました。
B2 noun ˈɔː.bɪt

orbit

軌道
Meaning
The curved path of a celestial object around a star, planet, or moon.
Example
The satellite maintains its orbit around Earth.
衛星は地球の周りを軌道上に保っています。
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。
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 adjective /ˌoʊvərˈrɔt/

overwrought

興奮した / 過度に緊張した
Meaning
extremely agitated or nervous; excessively elaborate
Example
She was too overwrought to speak clearly after the accident.
事故後、彼女は興奮しすぎて、はっきりと話すことができなかった。
B1 adjective /ˌoʊld ˈfæʃənd/

old-fashioned

昔風の
Meaning
not modern; belonging to an earlier time
Example
He still wears an old-fashioned hat.
彼は今でも昔風の帽子をかぶっています。
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。
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。
C1 noun /ˌoʊvərprəˈdʌkʃən/

overproduction

過剰生産
Meaning
The act of producing more of something than is needed or can be consumed.
Example
The economic crisis was caused by the overproduction of goods.
経済危機は商品の過剰生産によって引き起こされた。
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。
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。
C1 noun /ˈɒstrəsɪzəm/

ostracism

追放
Meaning
The act of excluding someone from a group or society.
Example
The student faced ostracism after breaking the rules.
その学生は規則を破った後、追放に直面しました。
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。
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。
B2 verb /oʊˈmɪt/

omit

省略する
Meaning
to leave out or exclude; to fail to include something
Example
Please don't omit any important details from your report.
レポートから重要な詳細を省略しないでください。
C1 noun /əbˈzɜːvəns/

observance

遵守
Meaning
The practice of following a custom, rule, or religious law.
Example
The festival is held in observance of a centuries-old tradition.
その祭りは、数世代にわたる伝統を遵守して行われます。
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。
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。
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 noun /ˈɔɪntmənt/

ointment

軟膏
Meaning
A smooth, oily substance applied to the skin for healing or soothing.
Example
The doctor prescribed an ointment for the burn on his arm.
医師は彼の腕のやけどのために軟膏を処方しました。
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。
B2 noun ˈoʊzoʊn dɪˈpliʃən

ozone depletion

オゾン層の減少
Meaning
The reduction in the amount of ozone in the Earth's stratosphere, leading to increased UV radiation.
Example
Ozone depletion increases UV radiation.
オゾン層の減少はUV放射線を増加させます。
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.
C2 noun /əˈblɪkwɪti/

obliquity

歪み
Meaning
Deviation from moral or usual conduct; indirectness or lack of straightforwardness.
Example
The politician was criticized for the obliquity of his answers.
その政治家は、彼の答えの歪みについて批判された。
C2 noun /ˌɑːpərˈtuːnɪzəm/

opportunism

機会主義
Meaning
The practice of taking advantage of opportunities regardless of principles or ethics.
Example
His decision was driven by opportunism, not values.
彼の決定は、価値観ではなくオポチュニズムに動機づけられていました。
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。
C2 adjective /əbˈtruːsɪv/

obtrusive

目障りな
Meaning
noticeable in an unpleasant or unwelcome way; intrusive
Example
The advertisement was so obtrusive that it ruined the user’s experience.
その広告はあまりにも目立ちすぎて、ユーザーの体験を台無しにしました。
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。
B2 noun /ˈɔːrnəmənt/

ornament

装飾品
Meaning
A decorative object that adds beauty to something.
Example
The Christmas tree was decorated with colorful ornaments.
クリスマスツリーはカラフルな装飾品で飾られていました。
A1 adverb /ˈɔːfən/

often

しばしば
Meaning
frequently, many times
Example
I often visit my grandparents on weekends.
私は週末にしばしば祖父母を訪れます。
B2 noun ˈəʊnəʃɪp

ownership

所有権
Meaning
The act, state, or right of possessing something; legal title to something.
Example
Ownership of resources was crucial.
資源の所有権は重要でした。
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。
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。
B1 adjective /ˈɔːɡənaɪzd/

organized

組織的な
Meaning
Arranged in a systematic way, especially on a large scale.
Example
An organized approach to work increases productivity and reduces stress.
仕事に対する組織的なアプローチは、生産性を高め、ストレスを減らします。
C1 adjective/adverb /ˌɒfˈhænd/

offhand

軽率
Meaning
Without previous thought or preparation; casual and sometimes dismissive.
Example
She gave an offhand reply to his serious question.
彼女は彼の真剣な質問に対して、軽率な返答をした。
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。
C1 noun /ˈoʊvərˌtʊr/

overture

序曲 / 提案
Meaning
An introduction to something more substantial; a proposal or preliminary action.
Example
The peace overture was welcomed by both nations.
平和提案は両国によって歓迎されました。
C2 adjective /ɑːlˈfæktəri/

olfactory

Meaning
Relating to the sense of smell.
Example
The perfume activated her olfactory nerves immediately.
C1 adjective /ˈɔːrdɪnəl/

ordinal

順序数
Meaning
Relating to the order or position of something in a sequence (first, second, third, etc.).
Example
The ordinal number 'third' indicates position in a sequence.
'第三'の順序数は、順番での位置を示します。
A1 adjective /ˈʌðər/

other

他の
Meaning
used to refer to something different from the one already mentioned or known
Example
I don't want this one, I will take the other one.
これを欲しくない、他のを取るつもりだ。
C2 noun /ˈoʊpiət/

opiate

Meaning
a drug containing opium or its derivatives, used to relieve pain or cause sleep
Example
The doctor prescribed an opiate to relieve the patient's pain.
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。
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。
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。
A2 noun /ˈɒpərə/

opera

オペラ
Meaning
a dramatic performance in which the actors sing most of their lines
Example
We watched a beautiful opera at the theater last night.
昨晩、劇場で美しいオペラを観ました。
C1 noun /oʊˈeɪ.sɪs/

Oasis

オアシス
Meaning
a fertile spot in a desert where water is found; a pleasant refuge
Example
The travelers found an oasis after days in the desert.
旅行者たちは砂漠で数日後にオアシスを見つけました。
C2 adjective /ɒmˈnɪp.ə.tənt/

omnipotent

全能
Meaning
Having unlimited power; able to do anything; all-powerful.
Example
In many religions, God is considered omnipotent.
多くの宗教では、神は全能だと考えられています。
B1 verb /oʊ/

owe

借りがある
Meaning
to be under obligation to pay or repay; to be indebted
Example
I owe my success to my parents' support.
私は両親の支援のおかげで成功しました。
C1 noun /oʊˈveɪʃən/

ovation

拍手
Meaning
an enthusiastic show of approval, especially by clapping hands
Example
The actor received a standing ovation after his performance.
俳優はパフォーマンス後にスタンディングオベーションを受けました。
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 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。
B2 noun /ˈaʊtˌfɪt/

outfit

衣装
Meaning
A set of clothes worn together, often for a particular occasion.
Example
She wore a beautiful outfit to the party.
彼女はパーティーに美しい衣装を着て行った。
A2 noun /ˈʌn.jən/

Onion

玉ねぎ
Meaning
a round vegetable with a strong taste and smell, made up of many layers
Example
I need to chop some onions for the curry recipe.
カレーのレシピのためにいくつか玉ねぎを切る必要があります。
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。
C2 noun /ˈoʊvərlɔːrd/

overlord

領主
Meaning
A ruler, master, or person of great power and authority over others.
Example
The peasants were forced to pay taxes to their overlord.
農民たちは自分たちの領主に税金を払うよう強制されました。
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 /ˌfæʃ.ənd/

Outdated

時代遅れ
Meaning
obsolete; no longer current
Example
This computer software is completely outdated.
このソフトウェアは完全に時代遅れです。
C1 noun /əbˈstrʌkʃən/

obstruction

障害
Meaning
Something that blocks or gets in the way; the action of obstructing.
Example
There was an obstruction on the railway track.
鉄道の線路に障害がありました。
C2 noun /ˈoʊɡər/

ogre

Meaning
A mythical monster, often depicted as large, hideous, and cruel; metaphorically, a cruel or terrifying person.
Example
The villagers feared the ogre who lived in the dark forest.
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。
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。
C1 verb /əˈprɛs/

oppress

抑圧する
Meaning
to keep someone down by harsh and unfair use of authority; to suppress
Example
The dictator oppressed the people for decades.
独裁者は何十年も人々を抑圧した。
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。
A2 noun /ˈoʊ.ʃən/

ocean

海洋
Meaning
A very large expanse of sea, especially the main areas of sea between continents.
Example
The ocean covers more than 70% of the Earth's surface.
海洋は地球の表面の70％以上を覆っています。
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 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。
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 /ˈaʊtbɜːrst/

outburst

感情または活動の突然の爆発
Meaning
a sudden release of strong emotion or activity
Example
She had an angry outburst during the meeting.
会議中に彼女は怒りの爆発をした。
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。
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。
B2 verb /ˌoʊvərˈiːt/

overeat

幸福
Meaning
To eat more food than the body needs.
Example
She tends to overeat when she is stressed.
彼女は賞を受け取ったとき、喜びを隠すことができませんでした。
C2 adjective /ɒmˈnɪʃ.ənt/

Omniscient

全知の
Meaning
having complete knowledge; all-knowing
Example
The narrator in the novel appears to be omniscient, knowing every character's thoughts.
小説の語り手は全知であるかのようで、すべての登場人物の思考を知っている。