obeisance
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C2 noun /oʊˈbeɪsəns/

obeisance

敬礼
Meaning
A gesture of respect such as a bow or curtsy.
Example
They bowed in obeisance to the king.
他们向国王行了敬礼。
C1 verb /aʊtˈlæst/

outlast

比...持续更久
Meaning
to continue longer than; to endure beyond someone or something else
Example
The old castle has outlasted many generations.
这座古老的城堡已经比许多代人持续得更久。
C2 adjective /ˈɑːbdjʊrət/

obdurate

固执
Meaning
Stubbornly refusing to change one's opinion or course of action.
Example
He remained obdurate despite everyone's pleas.
尽管大家的恳求，他依然固执。
B1 noun /ˌɒpəˈreɪʃən/

operation

手术
Meaning
an act or process of functioning or operating
Example
The hospital performed a successful operation.
医院进行了成功的手术。
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.
天文台在周末对公众开放。
C2 adjective /ɑːlˈfæktəri/

olfactory

Meaning
Relating to the sense of smell.
Example
The perfume activated her olfactory nerves immediately.
A2 adjective /ˈɔː.dɪ.nər.i/

Ordinary

普通的; 常见的; 不特别的
Meaning
normal; usual; not special
Example
It was just an ordinary day at the office.
那只不过是办公室里的普通一天。
B2 noun /əbˈsɛʃən/

obsession

痴迷
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.
他对成功的痴迷促使他日夜工作。
B2 noun ɔːˈɡæn.ɪk fuːdz

organic foods

有机食品
Meaning
Food produced without the use of chemicals such as artificial pesticides, fertilizers, or other artificial agents.
Example
Organic foods are healthier than processed foods.
有机食品比加工食品更健康。
B2 adjective /ˈɔː.rəl/

Oral

口头的；与嘴巴相关的
Meaning
spoken rather than written; relating to the mouth
Example
The oral examination will test your speaking skills.
口头考试将测试你的口语技能。
A2 adjective /əˈlɪmpɪk/

olympic

奥林匹克
Meaning
related to the Olympic Games, a major international sporting event
Example
She trained hard to compete in the Olympic Games.
她努力训练，为了参加奥林匹克运动会。
B2 noun /ˈɔːɡən/

organ

器官
Meaning
a part of the body that performs a specific function
Example
The heart is an important organ in the human body.
心脏是人体重要的器官。
B2 noun /ɒdz/

odds

可能性
Meaning
the likelihood or probability of something happening; chances for or against something
Example
The odds of winning the lottery are very low.
中彩票的机会非常小。
C2 adjective /əbˈstrɛpərəs/

obstreperous

喧闹且难以控制
Meaning
Noisy and difficult to control.
Example
The obstreperous students disrupted the class.
那些喧闹的学生打乱了课堂。
C1 adjective /əbˈdʒek.ʃən.ə.bəl/

Objectionable

令人反感的
Meaning
arousing distaste or opposition; unpleasant or offensive
Example
His objectionable behavior made everyone uncomfortable.
他的令人反感的行为让每个人都感到不舒服。
C1 adjective /əbˈnɒkʃəs/

Obnoxious

令人讨厌的；惹人厌的；极其讨厌的
Meaning
extremely unpleasant; offensive; annoying
Example
His obnoxious behavior at the party annoyed everyone.
他在聚会上的令人讨厌的举止惹恼了在场的每一个人。
C2 noun /ˌɔːrəˈtɔːri.oʊ/

oratorio

宗教音乐作品
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.
亨德尔的《弥赛亚》是最著名的宗教音乐作品之一。
C2 adjective /ˈɒsiəs/

osseous

骨质的
Meaning
consisting of or turned into bone; bony
Example
The fossil showed osseous structures of the ancient creature.
化石展示了古老生物的骨质结构。
C2 noun /ˈɒlɪv brɑːntʃ/

olive-branch

橄榄枝
Meaning
A symbol of peace or reconciliation; an offer to end conflict.
Example
He extended an olive-branch to his rival after years of hostility.
他在多年敌对之后向他的对手伸出了橄榄枝。
B2 adjective + noun ˈɒptɪməl ˈtempərətʃər

optimal temperature

最佳温度
Meaning
The best or most favorable temperature for a particular purpose
Example
Winter provides optimal temperature for farming.
冬天提供了农业的最佳温度。
C2 noun /ˌɒpəˈrɛtə/

operetta

轻歌剧
Meaning
a short opera with light and humorous themes
Example
The theater staged a famous operetta by Gilbert and Sullivan.
剧院上演了吉尔伯特与沙利文的著名轻歌剧。
B2 verb /ɒpt/

opt

选择
Meaning
to choose or decide to do something instead of something else
Example
Many students opt to study abroad for better opportunities.
许多学生选择出国留学以获得更好的机会。
C1 noun ˌɒk.sɪˈdeɪ.ʃən

oxidation

氧化
Meaning
A chemical reaction that involves the combination of a substance with oxygen, often causing deterioration.
Example
Oxidation causes metal surfaces to weaken.
氧化会削弱金属表面。
C1 noun /əˈpreʃ.ən/

Oppression

压迫; 虐待; 暴政;
Meaning
cruel or unjust treatment or exercise of authority; the state of being subject to harsh treatment
Example
The people fought against political oppression.
人民反对政治压迫而斗争。
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.
警官因超速给了他一张罚单。
B2 noun/verb /ˈoʊvərˌdoʊs/

overdose

过量服药
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.
他因毒品过量被送进了医院。
C2 adjective /əˈfɪʃəs/

officious

多管闲事
Meaning
Excessively eager to offer unwanted help or advice; meddlesome.
Example
The officious guard kept interrupting the visitors with unnecessary instructions.
那位多管闲事的警卫不断用不必要的指令打扰游客。
C2 noun /ˌɒktədʒəˈnɛəriən/

octogenarian

八十岁老人
Meaning
A person who is between 80 and 89 years old.
Example
The octogenarian still jogs every morning to stay healthy.
这位八十岁老人仍然每天早上跑步以保持健康。
C1 noun /ˌɑːsɪˈleɪʃən/

oscillation

摆动
Meaning
The movement back and forth at a regular speed.
Example
The oscillation of the pendulum controls the clock.
摆锤的摆动控制着时钟。
C1 noun /ˈɒfʃuːt/

offshoot

分支
Meaning
A branch or result that develops from something larger or more important.
Example
The startup was an offshoot of a major tech company.
这家初创公司是一个大型科技公司分支。
A2 noun /ˈɒf.ɪs/

office

办公室
Meaning
a room or building where people work, usually at desks
Example
She left the office early to attend a family event.
她提前离开办公室去参加家庭活动。
C1 adjective /ˌɒbsəˈliːt/

obsolete

过时的
Meaning
No longer in use or out of date.
Example
Floppy disks are now completely obsolete.
软盘现在完全过时了。
B1 adjective /əˈfɪʃəl/

official

官方
Meaning
relating to or connected with an authority or public office
Example
He is the official spokesperson for the company.
他是公司的官方发言人。
C1 noun /ˌɒk.sɪ.dʒɪˈneɪ.ʃən/

oxygenation

供氧或氧气治疗
Meaning
The process of supplying or treating with oxygen.
Example
Deep breathing exercises improve oxygenation of the body.
深呼吸练习有助于改善身体的供氧。
C2 noun /əbˈsɪdiən/

obsidian

黑曜石 (黑色的玻璃状火山岩)
Meaning
A hard, dark, glasslike volcanic rock formed by rapid solidification of lava.
Example
The knife was made from sharp obsidian.
刀是由锋利的黑曜石制成的。
C1 adjective /ˈɔːrdɪnəl/

ordinal

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.
序数词'第三'表示在顺序中的位置。
B1 verb /ˈɒpəreɪtɪŋ/

operating

操作
Meaning
to control or manage the functioning of something
Example
The company has been operating in this market for five years.
公司已经在这个市场运营了五年。
C1 adjective /ˌɑːpərˈtuːn/

opportune

合适的时刻
Meaning
Happening at a suitable or convenient time.
Example
She arrived at an opportune moment to help.
她在合适的时刻到达，准备帮助。
B2 noun /oʊˈbiː.di.əns/

Obedience

服从
Meaning
compliance with an order, request, or law; submission to authority
Example
Children should show obedience to their parents.
孩子们应该对父母表现出服从。
C1 adjective /ˌəʊ.vərˈɑː.tʃɪŋ/

overarching

总体, 包容, 全面
Meaning
Comprehensive or all-embracing; forming an arch over something.
Example
The overarching theme of the book is human resilience.
这本书的总体主题是人类的韧性。
B1 noun əbˈdʒek.tɪv

objective

目标
Meaning
A thing aimed at or sought; a goal.
Example
The main objective is to test sustainability.
主要目标是测试可持续性。
C2 verb /ˈɒsɪfaɪ/

ossify

骨化
Meaning
to turn into bone or become rigid and inflexible
Example
With age, some tissues tend to ossify.
随着年龄的增长，一些组织会变得僵硬。
C2 noun /əbˈstɛtrɪks/

obstetrics

产科
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.
她正在学习产科，想成为一名分娩专家。
C2 noun /ˌɔːrdɪˈneɪʃən/

ordination

任职
Meaning
The ceremony of conferring holy orders or official religious authority.
Example
The church held a special service for the ordination of new priests.
教堂为新神父举行了一个特别的服务，进行圣职任命。
C1 adjective/adverb /ˌɒfˈhænd/

offhand

草率
Meaning
Without previous thought or preparation; casual and sometimes dismissive.
Example
She gave an offhand reply to his serious question.
她对他严肃的问题做出了一个草率的回答。
C2 noun /ɒmˈnɪpətəns/

omnipotence

全能
Meaning
The quality of having unlimited power or authority.
Example
Many religions describe God’s omnipotence as absolute.
许多宗教将上帝的全能描述为绝对的。
B2 adjective /ˈaʊtˌɡoʊɪŋ/

outgoing

外向
Meaning
Friendly and sociable; inclined to mix with others.
Example
He is an outgoing person who loves meeting new people.
他是一个外向的人，喜欢结识新朋友。
A1 adverb /ˈɔːfən/

often

经常
Meaning
frequently, many times
Example
I often visit my grandparents on weekends.
我经常在周末拜访我的祖父母。
C1 noun /ˈaʊtˌkraɪ/

outcry

抗议
Meaning
A strong expression of public anger or disapproval.
Example
The decision sparked an outcry among the citizens.
这个决定在市民中引发了抗议。
A1 adjective /əʊˈkeɪ/

okay

没问题
Meaning
used to express agreement or acceptance
Example
It's okay to leave early today.
今天早些离开没问题。
C2 adjective /ɔːrˈθɑːɡənl/

orthogonal

正交
Meaning
at right angles; independent or unrelated
Example
In mathematics, two vectors are orthogonal if their dot product is zero.
在数学中，如果两个向量的点积为零，它们就是正交的。
B2 noun /ˈɔːkɪstrə/

orchestra

管弦乐队
Meaning
a large group of musicians playing different instruments together
Example
The orchestra performed beautifully at the concert.
管弦乐队在音乐会上演奏得非常出色。
C1 noun /ˈoʊ.vər spɪl/

Over-spill

溢出
Meaning
the overflow of liquid from a container; excess that cannot be contained
Example
The overspill from the river flooded nearby farms.
河水溢出导致附近的农田被淹没。
B2 noun /ˈaʊt.kʌm/

Outcome

结果; 后果;
Meaning
the result or consequence of an action or situation; the final product
Example
The outcome of the election surprised everyone.
选举的结果让所有人感到惊讶。
A2 preposition /ˈɒntu/

onto

在…上
Meaning
moving to a position on the surface of something
Example
She jumped onto the table to get the book.
她跳到桌子上去拿书。
B2 noun /əbˈzɜːvər/

observer

观察者
Meaning
a person who watches or notices something
Example
The observer took notes during the meeting.
观察者在会议期间做了笔记。
B2 verb /ˌoʊvərˈpeɪ/

overpay

支付过多
Meaning
To pay more than is necessary or reasonable.
Example
She realized she had overpaid for the concert tickets.
她意识到她为音乐会门票支付过多。
C1 noun /ˈɔːrθədɑːksi/

orthodoxy

正统
Meaning
traditional or generally accepted beliefs and practices
Example
The religious leader defended the orthodoxy of the faith.
宗教领袖捍卫了信仰的正统性。
C1 noun /ˈɑn.set/

Onset

开始; 起始
Meaning
the beginning or early stages of something; the start of a medical condition
Example
The onset of winter brought heavy snowfall.
冬天的开始带来了大雪。
C2 adjective /əˈrækjələr/

oracular

神谕的
Meaning
Resembling an oracle; giving wise, mysterious, or prophetic statements
Example
Her oracular words left the audience deep in thought.
她的神谕般的话让观众陷入了深思。
C1 noun /ˈoʊvərˌsiːər/

overseer

监督员
Meaning
a person who supervises work or workers; a manager
Example
The overseer made sure the workers followed safety rules.
监督员确保工人遵守安全规则。
C1 noun /əˈkɜr.əns/

Occurrence

事件
Meaning
an instance or event of something happening; the fact of occurring
Example
The occurrence of earthquakes is common in this region.
地震的发生在这个地区很常见。
C2 adjective /ˌoʊpəˈlɛsənt/

opalescent

欧泊色的
Meaning
showing or reflecting a milky, iridescent light like an opal
Example
The opalescent sky glowed with shades of pink and blue.
欧泊色的天空闪烁着粉色和蓝色的色调。
C2 noun /ˈɒksɪdənt/

occident

西方
Meaning
The countries of the West, especially Europe and America.
Example
The Occident has a long history of philosophical thought.
西方有着悠久的哲学思想历史。
C1 adverb /ˈɒp.tɪ.məl.i/

optimally

最优地
Meaning
In the most effective or efficient way possible.
Example
Tasks should be allocated optimally for maximum output.
任务应当最优地分配，以实现最大产出。
C2 noun /ˈɒkjʊlɪst/

oculist

眼科医生
Meaning
An old-fashioned term for an eye doctor or ophthalmologist.
Example
The village oculist was known for treating various eye diseases.
村里的眼科医生以治疗各种眼病而闻名。
B2 noun /ˈoʊvərpæs/

overpass

立交桥
Meaning
A bridge that carries one road or railway over another.
Example
The new overpass reduced traffic congestion in the city.
新的立交桥减少了城市的交通拥堵。
C2 noun /oʊf/

Oaf

笨拙、愚蠢或麻木的人
Meaning
a clumsy, stupid, or insensitive person
Example
Don't be such an oaf - handle the dishes carefully!
不要做那种笨蛋 – 小心洗碗！
C1 verb /əˈprɛs/

oppress

压迫
Meaning
to keep someone down by harsh and unfair use of authority; to suppress
Example
The dictator oppressed the people for decades.
独裁者压迫人民数十年。
C2 adjective /ˈɒfɪʃ/

offish

冷淡
Meaning
Unfriendly, distant, or reserved in manner.
Example
He seemed offish at the party and avoided most conversations.
他在派对上显得很冷淡，避开了大多数谈话。
C1 adjective /ˌɒstɛnˈteɪʃəs/

ostentatious

炫耀的
Meaning
Characterized by a showy or pretentious display intended to impress others.
Example
He wore an ostentatious gold chain to the party.
他在派对上戴着一条炫耀的金链子。
C2 adjective /ˌoʊdəˈrɪfərəs/

odoriferous

芬芳的
Meaning
having or giving off a smell, especially a strong or pleasant one
Example
The garden was filled with odoriferous flowers.
花园里充满了芬芳的花朵。
C1 verb ˈɔː.kɪ.streɪ.tɪd

orchestrated

精心策划
Meaning
Planned or coordinated carefully and deliberately.
Example
The attacks were orchestrated with precision.
袭击被精确地策划了。
B1 verb /əbˈzɜːrv/

observe

观察
Meaning
to watch carefully; to notice or perceive something
Example
Scientists observe the behavior of animals in the wild.
科学家观察野生动物的行为。
B1 verb /əˈkɜːr/

occur

发生
Meaning
to happen or take place; to be found or present
Example
The accident occurred at the intersection during rush hour.
事故发生在高峰时段的交叉口。
B2 noun /ˈɒpəreɪtər/

operator

操作员
Meaning
a person who operates equipment, a business, or controls something
Example
The machine operator ensured that everything ran smoothly.
机器操作员确保一切顺利运行。
B2 noun /ˈɒs.trɪtʃ/

Ostrich

鸵鸟
Meaning
a large flightless bird native to Africa with long legs and neck
Example
The ostrich is the world's largest bird.
鸵鸟是世界上最大的鸟。
C2 verb /ˈɔːreɪt/

orate

演讲
Meaning
To speak in a formal, often pompous manner
Example
He began to orate at the ceremony.
他在仪式上开始演讲。
C1 noun /ˈaʊtpoʊst/

outpost

前哨站
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.
士兵们被驻扎在一个偏远的前哨站。
C2 adjective /ˈɒf.biːt/

offbeat

不寻常
Meaning
Unusual, unconventional, or different from the norm.
Example
She has a very offbeat sense of humor.
她有非常不寻常的幽默感。
C1 noun /ˌɑːpərˈtuːnɪst/

opportunist

机会主义者
Meaning
A person who takes advantage of situations for personal gain, often disregarding principles.
Example
He is seen as an opportunist who always puts his interests first.
他被看作是一个机会主义者，总是把自己的利益放在第一位。
C2 adjective /ˈəʊ.dər.əs/

Odorous

芬芳的; 香气的
Meaning
having a strong smell; fragrant; aromatic
Example
The garden was filled with odorous flowers.
花园里充满了芬芳的花朵。
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.
小说的叙述者具有全知的气质，揭示每个角色的想法。
C1 verb /uːz/

ooze

渗透
Meaning
to slowly flow or leak out through small openings or pores
Example
Blood began to ooze from the small cut.
血液开始从小伤口渗透出来。
A1 preposition /ʌv/

of

的
Meaning
expressing the relationship between a part and a whole
Example
The book is on the table, in front of the window.
书在桌子上，在窗户前。
B2 adverb /ˈɒdli/

oddly

奇怪地
Meaning
in a strange or unusual way; unexpectedly
Example
Oddly, he didn’t seem upset by the bad news.
奇怪的是，他似乎并没有因为坏消息而难过。
C1 verb /aʊtˈlɪv/

outlive

比…活得长
Meaning
to live longer than someone or something else
Example
She outlived all her siblings.
她活过了所有的兄弟姐妹。
C2 adjective /ɒmˈnɪʃ.ənt/

Omniscient

全知的
Meaning
having complete knowledge; all-knowing
Example
The narrator in the novel appears to be omniscient, knowing every character's thoughts.
小说中的叙述者似乎是全知的，知道每个角色的思想。
C2 adjective /əˈprəʊ.bri.əs/

opprobrious

侮辱性的
Meaning
Expressing strong criticism or scorn.
Example
He made opprobrious remarks about his opponent.
他对对手做出了侮辱性评论。
A2 adjective /ˈɑp.ə.zɪt/

Opposite

相反的; 完全不同的; 面对面; 反向的;
Meaning
Contrary; completely different; facing each other; reverse;
Example
They have opposite views on politics but remain good friends.
他们在政治上的观点相反，但仍然是好朋友。
B2 adverb /əˈfɪʃəli/

officially

正式地
Meaning
in a formal or authorized way
Example
The building was officially opened by the mayor.
这座建筑由市长正式开幕。
C1 noun /oʊˈmɪʃ.ən/

Omission

省略; 排除
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.
从列表中省略他的名字是故意的。
C2 noun ˈoʊʃən ˌstrætɪfɪˈkeɪʃən

ocean stratification

海洋分层
Meaning
The formation of layers in ocean water due to differences in density.
Example
Ocean stratification affects marine biodiversity.
海洋分层影响海洋生物多样性。
A2 verb /oʊˈbeɪ/

obey

服从
Meaning
to follow orders or instructions; to comply with rules
Example
Children should obey their parents and teachers.
孩子们应该服从父母和老师的命令。
B2 adjective /ˌfæʃ.ənd/

Outdated

过时
Meaning
obsolete; no longer current
Example
This computer software is completely outdated.
这个软件完全过时了。
C1 verb /ˌoʊvərˈθroʊ/

overthrow

幸福
Meaning
To remove a leader or government from power, often by force.
Example
The rebels planned to overthrow the corrupt regime.
她在收到奖项时无法掩饰她的幸福感。
B2 adjective /ˈɒp.ʃən.əl/

Optional

可选的
Meaning
not compulsory; left to choice
Example
Wearing a tie is optional for this event.
穿领带是这个活动的可选项。
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.
光学幻觉在展览会上迷惑了所有人。
C2 adjective /ˈɔːrəˌtʌnd/

orotund

深沉而清晰的声音
Meaning
full, rich, and clear in sound; pompous in style
Example
The actor's orotund voice filled the theater.
演员的深沉声音充满了剧院。
C2 noun /ɔːrˈθɑːɡrəfi/

orthography

拼写法
Meaning
The conventional spelling system of a language.
Example
English orthography can be confusing for learners.
英语的拼写法对学习者来说可能是令人困惑的。
C1 verb /ˌoʊvərˈpaʊər/

overpower

征服
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.
士兵们成功压倒了敌军。
C1 adjective /ˌɒmnɪˈprezənt/

omnipresent

无所不在
Meaning
(of God) present everywhere at the same time.
Example
Social media has become an omnipresent force in modern society.
社交媒体已成为现代社会中无所不在的力量。
B2 noun /ɒpˈtɪʃən/

optician

眼镜师
Meaning
A person who makes or sells glasses and contact lenses.
Example
The optician adjusted my new glasses to fit better.
眼镜师调整了我的新眼镜，以便更好地适应。
B1 verb অকার্স

occurs

发生
Meaning
Happens or takes place, especially as a result of something.
Example
Snowfall occurs in regions with freezing temperatures.
在气温低于零度的地区会发生降雪。
A1 interjection /oʊ/

oh

哦
Meaning
used to express surprise, realization, or understanding
Example
Oh, I didn't know you were here!
哦，我不知道你在这里！
C1 verb /ˌoʊvərˈruːl/

overrule

驳回
Meaning
to reject or disallow by exercising one's superior authority; to override a decision
Example
The judge overruled the objection from the defense attorney.
法官驳回了辩护律师的反对。
C2 adjective /ˈoʊ.pən ˈhɑrt.ɪd/

Open-hearted

开放的心; 慷慨和真诚; 热情接纳;
Meaning
Kind and generous; sincere and honest; warmly receptive;
Example
She welcomed the strangers with an open-hearted smile and invited them for dinner.
她以开放的微笑欢迎陌生人，并邀请他们共进晚餐。
B2 noun /ˈaʊtskɜːrts/

outskirts

城市边缘
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.
他们为了更安静的生活搬到了城市的边缘。
C2 noun /ɒkˈteɪvoʊ/

octavo

八开 (通过将纸张折叠成八个部分而产生的书籍大小)
Meaning
A size of book page resulting from folding a sheet of paper into eight leaves (sixteen pages).
Example
The old library contained rare octavo editions of Shakespeare.
这座古老的图书馆里有莎士比亚的稀有八开版书籍。
C2 noun /ˈɒbsɪkwi/

obsequy

葬礼仪式
Meaning
A funeral rite, usually used in plural form obsequies.
Example
The village gathered for the obsequy of their beloved teacher.
村庄聚集在一起，参加他们心爱的老师的葬礼。
B2 noun /ˌɑb.lɪˈɡeɪ.ʃən/

Obligation

义务
Meaning
a duty or commitment; something that must be done legally or morally
Example
Parents have an obligation to care for their children.
父母有责任照顾他们的孩子。
B2 noun /əˈfɛns/

offense

犯罪
Meaning
an illegal act; a crime
Example
The offense was committed in broad daylight.
这个犯罪是在白天犯下的。
B2 noun ˈəʊ.və.hed

overhead

管理费用
Meaning
Ongoing business expenses not directly attributable to creating a product or service.
Example
The company reduced its overhead to increase profits.
公司减少了管理费用以增加利润。
C2 noun /ɑːlˈfækʃən/

olfaction

嗅觉
Meaning
The sense of smell; the process of detecting and perceiving odors.
Example
Dogs have a highly developed sense of olfaction.
狗的嗅觉非常发达。
A1 preposition, adverb /ˈoʊvər/

over

在…上面
Meaning
across, on top of, or beyond
Example
The book is lying over the table.
书在桌子上面。
B2 noun ˈɒksɪdʒən prəˈdʌkʃən

oxygen production

氧气生产
Meaning
The process of generating oxygen through photosynthesis or other means.
Example
Plants are vital for oxygen production and the maintenance of life.
植物对于氧气生产和维持生命至关重要。
B2 noun /ˈaʊt.breɪk/

Out-break

爆发
Meaning
a sudden occurrence or eruption of something, especially disease or violence
Example
The outbreak of flu affected many students in the school.
流感的爆发影响了学校的许多学生。
B2 noun /ˈaʊtˌsɛt/

outset

开始
Meaning
the beginning or start of something
Example
From the outset, the project seemed ambitious but achievable.
从一开始，项目看起来雄心勃勃但可以实现。
C2 noun /ˌɔːrnɪˈθɒlədʒɪst/

ornithologist

鸟类学家
Meaning
a scientist who studies birds
Example
The ornithologist spent years studying migratory birds.
这位鸟类学家花了多年时间研究迁徙鸟类。
C2 verb /ˈɑːblɪˌɡeɪt/

obligate

强迫
Meaning
to bind legally or morally; to compel someone to do something
Example
The contract obligates the company to provide timely service.
合同使公司有义务提供及时服务。
C1 noun /ˈɔɪntmənt/

ointment

药膏
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.
医生为他手臂上的烧伤开了一种药膏。