organic farming
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B2 noun /ɔːrˈɡæn.ɪk ˈfɑːr.mɪŋ/

organic farming

有機農業
Meaning
Farming method that avoids synthetic chemicals and fertilizers, using natural methods instead.
Example
Organic farming improves soil health and reduces pollution.
オーガニックファーミングは土壌の健康を改善し、汚染を減らします。
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。
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Becoming outdated or on the way to becoming obsolete.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。
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。
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。
C1 verb /ˈɒs.ɪ.leɪt/

oscillate

二つの点または状態の間で前後に動くまたは揺れる
Meaning
To swing or move back and forth between two points or states
Example
The stock market tends to oscillate during uncertain times.
株式市場は不確実な時期に振動しがちです。
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 /ˈɒp.tɪ.məl/

optimal

最適、最良
Meaning
Best or most favorable; the most effective under particular conditions.
Example
The optimal temperature for plant growth is around 25°C.
植物の成長に最適な温度は約25°Cです。
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。
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！
B2 noun /ˈoʊtˌmiːl/

oatmeal

オートミール
Meaning
A type of porridge made from ground oats, often eaten for breakfast.
Example
She eats a bowl of oatmeal every morning for breakfast.
彼女は毎朝、朝食にオートミールを一杯食べます。
C1 adverb /ˈaʊtwədli/

Outwardly

外見上; 表面的に;
Meaning
on the surface; externally; in appearance
Example
Outwardly, he seemed calm, but inside he was nervous.
外見上は落ち着いて見えましたが、内心では緊張していました。
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。
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 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 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。
B1 noun /ˈɑb.stə.kəl/

Obstacle

障害物
Meaning
something that blocks or makes progress difficult; a barrier
Example
Bad weather was the main obstacle to our journey.
悪天候が私たちの旅行の最大の障害物でした。
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.
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。
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。
A2 adjective /ˈaʊtdɔːr/

outdoor

アウトドア
Meaning
situated, existing, or done outside a building
Example
We planned an outdoor picnic for the weekend.
週末のためにアウトドアピクニックを計画しました。
A2 adjective /ˈɔː.dɪ.nər.i/

Ordinary

普通の; 一般的な; 特別ではない
Meaning
normal; usual; not special
Example
It was just an ordinary day at the office.
それはオフィスでのただの普通の日でした。
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。
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 verb /əˈfɪʃieɪt/

officiate

執り行う
Meaning
To perform official duties, especially in a ceremony or as a referee.
Example
The priest will officiate the wedding ceremony.
司祭が結婚式を司る。
C1 verb /ˌaʊtˈweɪ/

outweigh

より重要である
Meaning
To be more important, valuable, or significant than something else.
Example
The benefits of the new policy outweigh the risks.
新しい政策の利益はリスクを上回っています。
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 /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。
C1 noun /oʊθ/

Oath

誓い
Meaning
a solemn promise or declaration; a sworn statement
Example
The doctor took an oath to help patients.
医師は患者を助けることを誓いました。
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。
B1 noun /əˈkeɪ.ʒən/

Occasion

機会; 特別な出来事
Meaning
a particular time or instance of an event; a special celebration
Example
Their wedding was a joyous occasion.
彼らの結婚式は喜ばしい機会でした。
B2 adjective /ˌɑːp.təˈmɪs.tɪk/

optimistic

楽観的
Meaning
hopeful and confident about the future
Example
She is optimistic about the success of her new project.
彼女は新しいプロジェクトの成功に楽観的です。
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。
C2 verb /ˈɔːreɪt/

orate

演説する
Meaning
To speak in a formal, often pompous manner
Example
He began to orate at the ceremony.
彼は式で演説を始めました。
C1 verb əˈblɪt.ə.reɪt

obliterate

完全に破壊する
Meaning
To destroy utterly; wipe out completely, to erase or remove something completely.
Example
The storm obliterated entire villages.
嵐は村全体を完全に破壊しました。
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。
C1 adjective əʊˈpeɪk

opaque

不透明, 理解しにくい
Meaning
Not able to be seen through; not transparent; difficult to understand.
Example
The glass was too opaque to see through.
そのガラスは不透明すぎて、透けて見えませんでした。
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 /ˈɔːrθədɑːks/

orthodox

Meaning
conforming to traditional beliefs or practices
Example
He comes from a very orthodox family.
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。
C2 adjective /ˈoʊ.vɔɪd/

ovoid

卵型
Meaning
egg-shaped; resembling an oval or ellipse
Example
The artist painted an ovoid shape in the center of the canvas.
アーティストはキャンバスの中央に卵型の形を描きました。
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。
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。
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 /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 /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。
C2 adjective /ˈɒfɪʃ/

offish

無愛想
Meaning
Unfriendly, distant, or reserved in manner.
Example
He seemed offish at the party and avoided most conversations.
彼はパーティーで無愛想に見え、大半の会話を避けていました。
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。
B2 adjective /aʊtˈstændɪŋ/

outstanding

優れた
Meaning
extremely good or impressive; not yet resolved or paid
Example
She received an award for her outstanding performance.
彼女は優れたパフォーマンスで賞を受賞しました。
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 /ˌɒb.zəˈveɪ.ʃənz/

observations

観察
Meaning
The action or process of observing something carefully.
Example
Observations of distant galaxies provide new insights.
遠くの銀河の観察は新たな洞察を提供します。
B2 adverb /ˈəʊvəli/

overly

過度に
Meaning
to an excessive degree or extent
Example
She was overly concerned about the results.
彼女は結果について過度に心配していた。
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。
B2 adjective /əˈpəʊzd/

opposed

反対の
Meaning
being against or in disagreement with something
Example
She is strongly opposed to animal testing.
彼女は動物実験に強く反対しています。
B1 verb /ˈɒpəreɪt/

operate

操作する
Meaning
to function; to control or manage; to perform surgery
Example
The surgeon will operate on the patient tomorrow.
外科医は明日患者を手術します。
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。
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 noun /ˈɔɪ.stər/

Oyster

オイスター
Meaning
a type of shellfish that can be eaten and sometimes contains pearls
Example
She ordered fresh oysters at the seafood restaurant.
彼女はシーフードレストランで新鮮なオイスターを注文しました。
C2 noun /ˈɒfərtɔːri/

offertory

奉納
Meaning
The part of a religious service when offerings are collected; the offering itself.
Example
The offertory was taken during the Sunday service.
日曜日の礼拝中に奉納が取られました。
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。
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 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。
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。
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。
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 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 adjective /ˈɒpjʊlənt/

opulent

豪華な
Meaning
Ostentatiously rich, luxurious, or lavish.
Example
They hosted an opulent wedding with gold decorations.
彼らは金色の装飾を施した豪華な結婚式を開催しました。
B2 noun /wʌn θɜːd/

one-third

三分の一
Meaning
one part of something that is divided into three equal parts
Example
One-third of the class was absent today.
クラスの三分の一が今日は欠席でした。
A2 noun /ˈoʊ.nər/

Owner

所有者
Meaning
a person who owns something; someone who has legal possession of property
Example
The owner of the restaurant greeted us warmly.
レストランの所有者は私たちを温かく迎え入れてくれました。
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。
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.
B2 noun /ɒdz/

odds

確率
Meaning
the likelihood or probability of something happening; chances for or against something
Example
The odds of winning the lottery are very low.
宝くじに当選する確率は非常に低いです。
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。
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。
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。
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。
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。
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。
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。
C1 noun /ˈoʊvərˌsiːər/

overseer

監督者
Meaning
a person who supervises work or workers; a manager
Example
The overseer made sure the workers followed safety rules.
監督者は、労働者が安全規則を守っていることを確認しました。
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。
A1 adverb /ɔːf/

off

オフ
Meaning
away from a place, position, or time; not functioning
Example
He turned off the light before leaving the room.
彼は部屋を出る前に電気をオフにしました。
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。
B2 noun /ˈɒp.tɪ.mɪ.zəm/

optimism

楽観主義
Meaning
Hopefulness and confidence about the future or the successful outcome of something.
Example
Her optimism helped her overcome difficult times.
彼女の楽観主義は、困難な時期を乗り越える助けとなりました。
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。
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。
C1 adjective /əbˈstrʌk.tɪv/

Obstructive

妨害的な
Meaning
deliberately creating difficulties or preventing progress; hindering or blocking something
Example
The obstructive policies hindered economic growth.
妨害的な政策は経済成長を阻害した。
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。
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。
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。
B2 verb /ˌoʊvərˈwɛlm/

overwhelm

Meaning
to overpower someone emotionally or physically; to be too much to handle
Example
She was overwhelmed with gratitude after receiving the help.
C2 noun ˌɒbfəsˈkeɪʃən

obfuscation

難解化, 混乱
Meaning
The action of making something obscure, unclear, or unintelligible.
Example
The obfuscation of the data made it difficult to interpret.
データの難解化により、解釈が困難になりました。
C1 noun /əˈkɜr.əns/

Occurrence

出来事
Meaning
an instance or event of something happening; the fact of occurring
Example
The occurrence of earthquakes is common in this region.
この地域では地震の出来事が一般的です。
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 adjective /əˈrækjələr/

oracular

神託のような
Meaning
Resembling an oracle; giving wise, mysterious, or prophetic statements
Example
Her oracular words left the audience deep in thought.
彼女の神託のような言葉は、観客を深く考えさせた。
C1 noun /ˈɔr.ə.tər/

Orator

演説家
Meaning
a public speaker, especially one who is eloquent or skilled in speaking
Example
The famous orator delivered an inspiring speech.
有名な演説家が感動的なスピーチを行った。
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。
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。
B2 adjective /ˈɒp.ʃən.əl/

Optional

任意
Meaning
not compulsory; left to choice
Example
Wearing a tie is optional for this event.
このイベントではネクタイの着用は任意です。
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。
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。
C1 noun /ˈɒktəɡən/

octagon

八角形
Meaning
A polygon with eight sides and eight angles.
Example
The stop sign is shaped like an octagon.
ストップサインは八角形をしています。
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 /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 ɔːrˈdiːl

ordeal

厳しい試練
Meaning
A physical or mental painful experience that must be endured
Example
Surviving the wilderness was a tough ordeal for them.
荒野で生き残ることは彼らにとって大変な試練でした。
C1 noun əˈblɪv.i.ən

oblivion

忘却, 破壊, 消失
Meaning
The state of being unaware or unconscious of what is happening; complete forgetfulness.
Example
His name faded into oblivion over time.
彼の名前は時と共に忘却の中に消えた。
B2 noun /ˈɒfərɪŋ/

offering

オファリング
Meaning
something that is given, especially as a gift or contribution
Example
The company’s latest offering is an eco-friendly car.
会社の最新のオファリングは、エコフレンドリーな車です。
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.
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。
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 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 /ˈɑːbvieɪt/

obviate

排除する
Meaning
To remove a need or difficulty; to prevent or avoid something.
Example
This new system obviates the need for manual data entry.
この新しいシステムは手動データ入力の必要性を排除します。
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。
B1 noun /ˈɔːfɪsər/

officer

警官
Meaning
a person in a position of authority, especially in law enforcement
Example
The officer gave him a ticket for speeding.
警官はスピード違反で彼にチケットを渡した。
B2 verb /ˌoʊvərˈpeɪ/

overpay

過剰に支払う
Meaning
To pay more than is necessary or reasonable.
Example
She realized she had overpaid for the concert tickets.
彼女はコンサートのチケットに多く支払ったことに気づきました。
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 /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。
C1 noun /ˈɔːr.ə.tɔːr.i/

oratory

弁論術
Meaning
The art of public speaking; skilled and confident delivery of speeches to an audience.
Example
His exceptional oratory skills won him the debate competition.
彼の卓越した弁論術は、ディベートコンペティションで彼に勝利をもたらしました。
C2 noun /ˈəʊpəs/

opus

創作作品
Meaning
A creative work, especially a large and important piece of music or art.
Example
The composer considered the symphony his greatest opus.
作曲家は交響曲を自分の最も偉大な創作作品と見なしていました。
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。