olfaction
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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。
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。
B1 adjective /əˈfɪʃəl/

official

公式
Meaning
relating to or connected with an authority or public office
Example
He is the official spokesperson for the company.
彼は会社の公式なスポークスマンです。
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 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。
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 /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。
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。
C2 verb ˈɑːb.fə.skeɪt

obfuscate

曖昧にする、混乱させる、隠す
Meaning
Render obscure, unclear, or unintelligible.
Example
Politicians often obfuscate facts to mislead people.
政治家はしばしば事実をわかりにくくして人々を誤導します。
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。
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。
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 /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 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 verb /ˌoʊvərˈloʊd/

overload

過負荷
Meaning
to load with too much weight or cargo; to give too much work or information
Example
Don't overload the washing machine or it might break down.
洗濯機をオーバーロードしないでください、壊れるかもしれません。
C1 noun ˈoʊʃən əˌsɪdɪfɪˈkeɪʃən

ocean acidification

海洋酸性化
Meaning
The ongoing decrease in the pH of the Earth's oceans, caused by the absorption of carbon dioxide from the atmosphere.
Example
Ocean acidification is caused by atmospheric CO2 absorption.
海洋酸性化は、大気中のCO2の吸収によって引き起こされます。
B2 noun /ˌɔː.ri.enˈteɪ.ʃən/

orientation

オリエンテーション
Meaning
the process of becoming familiar with a new situation or environment
Example
The company provides an orientation for all new employees.
会社はすべての新しい従業員にオリエンテーションを提供します。
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。
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 /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。
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。
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。
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 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。
C2 noun /ˈɔː.rɪ.fɪs/

orifice

Meaning
an opening or hole, especially in the body or a device
Example
The medicine was applied through a small orifice in the device.
薬は装置の小さな孔から適用されました。
C2 noun /ˈɒb.stɪ.nə.si/

obstinacy

頑固
Meaning
Stubborn refusal to change one's opinion or chosen course of action, despite attempts to persuade one to do so.
Example
His obstinacy made negotiations difficult.
彼の頑固さは交渉を難しくしました。
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 /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 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 /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。
C2 verb /ˈɑːskjʊleɪt/

osculate

キスする
Meaning
To kiss.
Example
They osculated under the mistletoe during the party.
彼らはパーティーの時にヤドリギの下でキスをしました。
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 /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。
C1 adjective ˈɒk.sɪ.də.tɪv

oxidative

酸化に関連する
Meaning
Related to or caused by oxidation, especially cellular damage from free radicals.
Example
Excess stress can lead to oxidative damage in cells.
過度のストレスは細胞に酸化的な損傷を引き起こす可能性があります。
A2 noun əˈlɪm.pɪk ɡeɪmz

Olympic Games

オリンピック競技大会
Meaning
The world's largest international sports competition held every four years, bringing together athletes from different countries to compete in various sports.
Example
The Olympic Games bring together the world's top athletes.
オリンピック競技大会は世界のトップアスリートを集めます。
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。
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。
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 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 /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。
B2 adjective; verb (past participle) /ˈɒkjʊpaɪd/

occupied

使用中の;占領された
Meaning
being in use or taken; filled or lived in; controlled or held by force
Example
The room is occupied, so please wait outside.
その部屋は使用中なので、外で待ってください。
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 noun ˌɒpəˈtjuːnɪtiz

opportunities

チャンス
Meaning
A set of circumstances that makes it possible to do something; chances for advancement or success.
Example
Opportunities for jobs decreased.
仕事のチャンスが減少しました。
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。
B1 verb /əˈkɜːr/

occur

発生する
Meaning
to happen or take place; to be found or present
Example
The accident occurred at the intersection during rush hour.
事故はラッシュアワーの交差点で発生しました。
C2 noun /ˌɒstɛnˈteɪʃən/

ostentation

見せびらかし
Meaning
excessive display of wealth or knowledge intended to attract admiration or envy
Example
The billionaire’s party was full of ostentation and luxury.
億万長者のパーティーは、見せびらかしと贅沢で満ちていた。
C1 adjective /əˈkʌlt/

occult

オカルト
Meaning
Relating to mysterious, supernatural, or magical powers and practices.
Example
She had always been fascinated by the occult and its hidden knowledge.
彼女は常にオカルトとその隠された知識に魅了されていた。
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。
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。
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。
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。
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 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。
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。
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。
C1 verb /ˌoʊvərˈʃædoʊ/

overshadow

覆い隠す
Meaning
to appear more important or significant than something else, reducing its impact
Example
The scandal overshadowed his achievements.
スキャンダルは彼の業績を影にしました。
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。
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 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。
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。
B2 noun /ˈɔːrɡənaɪzər/

organizer

主催者
Meaning
a person who arranges or coordinates activities, events, or groups; a tool or item used to keep things in order
Example
She worked as the main organizer of the international conference.
彼女は国際会議の主要な主催者だった。
C1 noun /ˈaʊtriːtʃ/

outreach

支援拡大
Meaning
The act of providing services or support to people who might not otherwise have access to them.
Example
The charity launched a new outreach program for the homeless.
チャリティはホームレスのために新しい支援拡大プログラムを開始しました。
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。
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。
A2 noun /ˈoʊpənɪŋ/

opening

開店
Meaning
an act or instance of beginning something
Example
The opening of the new store was a huge success.
新しい店のオープニングは大成功でした。
C1 noun /ˈaʊtpoʊst/

outpost

前哨基地
Meaning
A small military camp or position at some distance from the main force, used especially as a guard.
Example
The soldiers were stationed at a remote outpost.
兵士たちは遠隔地の前哨基地に配置されました。
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。
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。
B2 noun /ˈaʊtlet/

outlet

出口
Meaning
a means by which something is released, expressed, or distributed
Example
Art is a great outlet for emotions.
アートは感情のための素晴らしい出口です。
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 /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 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。
A2 noun /ˈʌv.ən/

Oven

オーブン
Meaning
an enclosed compartment used for heating, baking, or drying food
Example
She baked cookies in the oven for thirty minutes.
彼女はオーブンで三十分間クッキーを焼きました。
B2 adverb /ˌoʊvərˈnaɪt/

Overnight

一晩で; 突然; 非常に速く
Meaning
during the night; suddenly; very quickly
Example
The city was transformed overnight.
街は一晩で変わった。
A1 preposition /ʌv/

of

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。
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。
C1 adjective /ˈɔːrθədɑːks/

orthodox

Meaning
conforming to traditional beliefs or practices
Example
He comes from a very orthodox family.
C2 noun /ˈɔːfəl/

offal

内臓
Meaning
the internal organs and entrails of an animal used as food; waste parts
Example
The butcher prepared sausages using pork offal.
肉屋は豚の臓物を使ってソーセージを作った。
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。
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 /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。
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。
C2 verb /aʊtˈraɪd/

outride

追い越す
Meaning
to ride faster, farther, or better than someone else
Example
The young rider managed to outride his competitors in the race.
若いライダーはレースで競技者たちを追い越しました。
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 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。
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 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。
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 /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。
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。
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。
C1 adjective /ˈɒptɪkəl/

optical

光学的
Meaning
related to or used in seeing or sight
Example
The optical illusion fooled everyone at the exhibition.
その光学的錯覚は展示会で皆を騙した。
C2 noun /ɒmˈnɪpətəns/

omnipotence

全能
Meaning
The quality of having unlimited power or authority.
Example
Many religions describe God’s omnipotence as absolute.
多くの宗教では神の全能は絶対的なものと説明されています。
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。
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 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。
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 /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。
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。
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 /ɒpˈtɒmətri/

optometry

視力検査学
Meaning
The practice or profession of examining the eyes and prescribing corrective lenses.
Example
She studied optometry at the university to become an eye specialist.
彼女は大学でオプトメトリーを学び、眼科専門医になりました。
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。
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 noun /ˌɔːrnɪˈθɑːlədʒi/

ornithology

鳥類学
Meaning
the scientific study of birds
Example
She pursued ornithology to understand the migration patterns of birds.
彼女は鳥の移動パターンを理解するためにオルニソロジーを追求しました。
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。
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。
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。
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。
C1 noun /oʊˈmɪʃ.ən/

Omission

省略; 除外
Meaning
the action of excluding or leaving out someone or something; a failure to include
Example
The omission of his name from the list was intentional.
リストから彼の名前を省略することは意図的でした。
B1 noun /ˈɑː.lɪv/

Olive

オリーブ
Meaning
a small oval fruit with a hard pit, typically green or black, used for eating or making oil
Example
Olive oil is considered one of the healthiest cooking oils available.
オリーブオイルは、最も健康的な料理用オイルの一つと見なされています。
A2 preposition /ˈɒntu/

onto

上に
Meaning
moving to a position on the surface of something
Example
She jumped onto the table to get the book.
彼女は本を取るためにテーブルの上に飛び乗った。
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 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。
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。
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。
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 noun /əbˈstrʌkʃənɪst/

obstructionist

Meaning
a person who deliberately delays or prevents progress by being uncooperative or oppositional
Example
The obstructionist in the committee kept delaying the decision-making process.
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。
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。
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。
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。