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A1 adjective /oʊld/

old

旧的
Meaning
having lived for a long time; not new or young
Example
He still drives his old car.
他仍然开着他的旧车。
C2 verb /əbˈtruːd/

obtrude

强行介入
Meaning
to force oneself or one's ideas into a situation uninvited or inappropriately
Example
He didn’t want to obtrude into their private conversation.
他不想打扰他们的私人对话。
A2 noun /ɔɪl/

Oil

油
Meaning
a viscous liquid derived from petroleum or plants, used for cooking or fuel
Example
Heat the oil in a pan before adding the vegetables.
在加菜之前先把油加热。
C1 adjective /ɔːˈneɪt/

ornate

华丽的
Meaning
elaborately or highly decorated
Example
The palace hall was filled with ornate furniture and paintings.
宫殿的大厅里充满了华丽的家具和画作。
C1 noun /əbˈdʒɛktər/

objector

反对者
Meaning
a person who expresses opposition or disapproval to something
Example
The objector raised his concerns during the town meeting.
反对者在市议会会议中表达了他的关切。
C1 verb /ˌaʊtˈduː/

outdo

超越
Meaning
To do better than someone else; to surpass.
Example
She always tries to outdo her classmates in exams.
她总是尽力在考试中超越她的同学。
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。
C2 adjective /əbˈtruːsɪv/

obtrusive

干扰的
Meaning
noticeable in an unpleasant or unwelcome way; intrusive
Example
The advertisement was so obtrusive that it ruined the user’s experience.
广告如此显眼，以至于破坏了用户体验。
C1 verb /ˌaʊtˈstrɪp/

outstrip

超越
Meaning
To go faster or do better than someone or something; to surpass.
Example
The company outstripped its competitors in sales last year.
公司在去年超越了它的竞争对手。
C1 noun /ˈɔːrkɪd/

Orchid

兰花
Meaning
a diverse family of flowering plants known for their exotic and often fragrant flowers
Example
The white orchid on the windowsill bloomed for months.
窗台上的白色兰花开了好几个月。
B2 noun ˈɔː.bɪt

orbit

轨道
Meaning
The curved path of a celestial object around a star, planet, or moon.
Example
The satellite maintains its orbit around Earth.
卫星保持它绕地球的轨道。
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。
B2 noun /ˈoʊtˌmiːl/

oatmeal

燕麦粥
Meaning
A type of porridge made from ground oats, often eaten for breakfast.
Example
She eats a bowl of oatmeal every morning for breakfast.
她每天早晨吃一碗燕麦粥当早餐。
B2 noun ˈəʊnəʃɪp

ownership

所有权
Meaning
The act, state, or right of possessing something; legal title to something.
Example
Ownership of resources was crucial.
资源的所有权至关重要。
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。
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。
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。
C1 adjective /əbˈtjuːs/

Obtuse

迟钝的; 愚笨的; 理解慢
Meaning
annoyingly insensitive or slow to understand; lacking in intelligence or perception
Example
He was being deliberately obtuse about the instructions.
他故意在指令上表现得迟钝。
A2 noun /ˈɔr.dər/

Order

命令; 顺序
Meaning
a command or instruction; the arrangement of things following a particular sequence
Example
The teacher gave an order to sit down quietly.
老师下达了安静坐下的命令。
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。
C2 noun /ˌɑːpərˈtuːnɪzəm/

opportunism

机会主义
Meaning
The practice of taking advantage of opportunities regardless of principles or ethics.
Example
His decision was driven by opportunism, not values.
他的决定是由机会主义驱动的，而不是由价值观驱动的。
C1 noun ˌɒb.səˈlɛs.əns

obsolescence

淘汰
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.
科技的快速发展导致旧设备的淘汰。
C1 adjective /ɒˈstɛnsəbl/

ostensible

表面上
Meaning
stated or appearing to be true, but not necessarily so
Example
His ostensible reason for leaving was illness, but many doubted it.
他离开的表面上原因是生病，但许多人对此表示怀疑。
C1 noun /ˈɔr.i.ənt/

Orient

东方，尤其是东亚国家
Meaning
the East, especially countries of eastern Asia; to determine one's position or direction
Example
Many spices come from the Orient.
许多香料来自东方。
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。
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.
B2 verb /əˈfend/

offend

冒犯
Meaning
to cause displeasure or resentment; to hurt someone's feelings
Example
His rude comments offended many people at the meeting.
他的粗鲁评论冒犯了会议上的许多人。
B1 verb /ˈɒpəreɪt/

operate

操作
Meaning
to function; to control or manage; to perform surgery
Example
The surgeon will operate on the patient tomorrow.
外科医生明天将为病人做手术。
B2 noun /ˈaʊtɪŋ/

outing

短途旅行
Meaning
a short trip or excursion, often for leisure or enjoyment
Example
They had a lovely outing at the beach last weekend.
他们上周末在海滩上度过了一个美好的短途旅行。
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。
B2 adjective ɔːrˈɡæn.ɪk

organic

有机的
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.
有机农业改善土壤健康并减少污染。
C1 noun /ˈɑːlɪˌɡɑːrki/

oligarchy

寡头政治
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.
这个国家由一个富有的寡头集团统治，控制着所有资源。
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。
C1 adjective /ˌaʊtˈspoʊkən/

Outspoken

直言不讳
Meaning
frank; speaking directly
Example
She is known for being outspoken about social issues.
她因直言不讳地谈论社会问题而闻名。
B1 adjective /ˈɔːɡənaɪzd/

organized

有条理的
Meaning
Arranged in a systematic way, especially on a large scale.
Example
An organized approach to work increases productivity and reduces stress.
有条理的工作方法可以提高生产力并减少压力。
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。
B2 noun /ˌoʊ.vɚˈkraʊ.dɪŋ/

overcrowding

过度拥挤
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.
地铁系统在高峰时段面临严重的过度拥挤。
C2 noun /ˌɒn.əˌmæt.əˈpiː.ə/

onomatopoeia

拟声词
Meaning
The formation of a word from a sound associated with what is named.
Example
The word 'buzz' is an example of onomatopoeia.
‘buzz’ 这个词是拟声词的一个例子。
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。
B2 verb /əˈpoʊz/

oppose

反对
Meaning
to disagree with or resist; to act against
Example
Many citizens oppose the new tax policy.
许多公民反对新的税收政策。
A1 adjective/adverb /ˈoʊnli/

only

唯一
Meaning
without others; solely
Example
He is the only person who knows the secret.
他是唯一知道这个秘密的人。
B2 noun /ˈɔr.fən/

Orphan

孤儿
Meaning
a child whose parents are dead; someone without protective support
Example
The orphan was adopted by a loving family.
孤儿被一户充满爱心的家庭收养了。
B2 noun /ˈoʊ.vər ɡroʊθ/

Over growth

过度生长
Meaning
excessive growth beyond normal size; too much development or expansion
Example
The overgrowth of weeds made the garden look untidy.
杂草的过度生长让花园显得不整洁。
A1 pronoun /aʊər/

our

我们的
Meaning
belonging to or associated with the speaker and one or more other people
Example
This is our house.
这是我们的房子。
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。
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。
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。
B2 adjective ˌɒp.ərˈeɪ.ʃən.əl

operational

操作的
Meaning
In working order; ready for use.
Example
The space project will be operational by 2025.
太空项目将在2025年投入使用。
B2 noun/verb /ˈaʊtreɪdʒ/

outrage

愤怒
Meaning
A strong feeling of anger and shock; to arouse anger or shock.
Example
The unfair decision caused public outrage.
不公正的决定引起了公众的愤怒。
B2 noun /ˈɔːɡənɪzəm/

organism

有机体
Meaning
a living thing that has an organized structure and can grow and reproduce
Example
Every organism needs water to survive.
每个有机体都需要水才能生存。
B2 noun /ɑːks/

Ox

牛
Meaning
a large strong animal used for pulling heavy loads or plowing fields
Example
The farmer used an ox to plow the field.
农民用牛耕地。
B1 noun /ˈɑb.stə.kəl/

Obstacle

障碍
Meaning
something that blocks or makes progress difficult; a barrier
Example
Bad weather was the main obstacle to our journey.
坏天气是我们旅行的主要障碍。
C1 adjective /ˌaʊt əv ðə ˈweɪ/

out-of-the-way

偏远的或不寻常的
Meaning
remote or unusual; not in a convenient or usual location
Example
They stayed in an out-of-the-way village.
他们住在一个偏远的村庄里。
B1 adjective /ˌoʊvərˈsiːz/

overseas

海外
Meaning
in or to a foreign country across the sea
Example
He went overseas for higher education.
他去海外深造。
B2 noun ˈaʊt.pʊt

output

产量
Meaning
The amount of something produced by a person, machine, or industry.
Example
Climate change reduces agricultural output.
气候变化减少农业产量。
C1 verb /əbˈstrʌkt/

obstruct

阻碍
Meaning
to block or hinder progress; to prevent or impede movement
Example
The fallen tree obstructed the road for several hours.
倒下的树挡住了路几个小时。
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。
C2 adjective /ˈɑːsɪˌfaɪd/

ossified

变成骨头，僵硬
Meaning
Turned into bone or become rigid; unwilling to change.
Example
The company had an ossified management structure that resisted innovation.
该公司有一个僵化的管理结构，抵制创新。
C2 verb /əbˈvɜːrt/

obvert

反转
Meaning
To turn something so as to face in a different direction; in logic, to convert a proposition by negating both subject and predicate.
Example
The teacher asked the students to obvert the statement for practice.
老师要求学生练习将声明进行奥贝特。
C1 verb /ˈɒp.tɪ.maɪz/

optimize

优化
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.
公司正在努力优化其供应链。
C1 noun /ˈɒn.slɔːt/

onslaught

猛攻
Meaning
A fierce or destructive attack.
Example
The village faced an onslaught of enemy forces.
这个村庄面临敌军的猛烈进攻。
C2 noun /ˈɒn.rʌʃ/

onrush

突如其来的冲击
Meaning
A sudden powerful forward or downward rush or flow.
Example
The onrush of water swept away the bridge.
水流的突如其来冲击冲走了桥梁。
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。
A2 adjective /ˈaʊtdɔːr/

outdoor

户外
Meaning
situated, existing, or done outside a building
Example
We planned an outdoor picnic for the weekend.
我们计划了一个户外野餐，周末进行。
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。
C1 noun /oʊˈveɪʃən/

ovation

掌声
Meaning
an enthusiastic show of approval, especially by clapping hands
Example
The actor received a standing ovation after his performance.
演员在表演后收到了站立的掌声。
C2 noun /oʊliˈændər/

Oleander

夹竹桃
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.
美丽的夹竹桃花在花园里盛开，尽管它们有毒。
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。
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。
B2 adjective /aʊtˈreɪdʒəs/

outrageous

骇人听闻
Meaning
Shockingly bad or excessive; very unusual or amusing.
Example
The comedian told an outrageous joke.
这位喜剧演员讲了一个骇人听闻的笑话。
C1 noun /ˌəʊvərɪksˌplɔɪˈteɪʃən/

overexploitation

过度开发
Meaning
The unsustainable use of natural resources at a rate that exceeds their ability to regenerate, leading to depletion and environmental degradation.
Example
Overexploitation of natural resources leads to environmental degradation.
过度开发自然资源会导致环境退化。
B2 noun /ˈɔːrɡənaɪzər/

organizer

组织者
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.
她是这次国际会议的主要组织者。
B2 adverb /ˈaʊtraɪt/

Outright

直接; 完全; 毫不保留
Meaning
completely; directly; without reservation or concealment
Example
She rejected the proposal outright.
她直接拒绝了那个提案。
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.
在许多宗教中，上帝被认为是全能的。
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。
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.
艺术是情感的一个极好的出口。
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 noun /ˈɒp.tɪ.mɪ.zəm/

optimism

乐观
Meaning
Hopefulness and confidence about the future or the successful outcome of something.
Example
Her optimism helped her overcome difficult times.
她的乐观帮助她克服了困难的时光。
C1 adjective /əˈblaɪdʒɪŋ/

obliging

乐于助人
Meaning
Willing to help or do favors; accommodating.
Example
The staff at the hotel were very obliging and friendly.
酒店的工作人员非常乐于助人且友好。
B2 adjective /ˌoʊvərˈwɛlmɪŋ/

overwhelming

压倒性的
Meaning
Very intense; overpowering.
Example
Large tasks can feel overwhelming.
大型任务可能会让人感到压倒。
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 /ˌaʊt ən ˈaʊt/

out-and-out

完全
Meaning
complete; absolute; used to emphasize something extreme
Example
The speech was an out-and-out lie.
这个演讲是一个完全的谎言。
C1 verb /ˈɒs.ɪ.leɪt/

oscillate

在两个点或状态之间来回摆动或移动
Meaning
To swing or move back and forth between two points or states
Example
The stock market tends to oscillate during uncertain times.
股市在不确定的时期往往会波动。
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。
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。
B1 adverb /ˈʌðərwaɪz/

Otherwise

否则; 不然
Meaning
in a different way; if not; or else; apart from that
Example
Study hard, otherwise you will fail the exam.
努力学习，否则你会考试失败。
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。
C2 noun /ˈɔː.rɪ.fɪs/

orifice

孔
Meaning
an opening or hole, especially in the body or a device
Example
The medicine was applied through a small orifice in the device.
药物通过设备上的一个小孔应用。
C1 adjective /əbˈstrʌk.tɪv/

Obstructive

阻碍性的
Meaning
deliberately creating difficulties or preventing progress; hindering or blocking something
Example
The obstructive policies hindered economic growth.
这些阻碍性的政策阻碍了经济增长。
C2 noun /ˈoʊdiəm/

odium

憎恶
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.
丑闻让腐败的部长蒙受了公众的憎恶。
C1 verb əˈblɪt.ə.reɪt

obliterate

摧毁
Meaning
To destroy utterly; wipe out completely, to erase or remove something completely.
Example
The storm obliterated entire villages.
暴风雨摧毁了整个村庄。
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。
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。
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。
A2 modal verb /ɔːt/

ought

应该
Meaning
Used to indicate duty, correctness, or moral obligation.
Example
You ought to respect your elders.
你应该尊重长辈。
B1 noun /əˈpɪn.jən/

Opinion

意见
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.
在我看来，这是最好的解决方案。
C1 noun /ˈɔr.ə.tər/

Orator

演说家
Meaning
a public speaker, especially one who is eloquent or skilled in speaking
Example
The famous orator delivered an inspiring speech.
这位著名的演说家发表了一场鼓舞人心的演讲。
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。
B1 adjective /əˈbiː.di.ənt/

Obedient

顺从的
Meaning
willing to comply with orders or instructions; submissive
Example
The obedient student always follows the teacher's instructions.
听话的学生总是遵循老师的指示。
C2 noun /ˈɔɪl.mən/

Oilman

石油商
Meaning
a person who works in the oil industry; someone who sells oil or petroleum products
Example
The oilman discovered a new oil field in the desert.
石油商在沙漠中发现了一个新的油田。
C2 verb /aʊtˈraɪd/

outride

超越
Meaning
to ride faster, farther, or better than someone else
Example
The young rider managed to outride his competitors in the race.
年轻的骑手在比赛中成功超越了他的竞争对手。
B2 noun /ˈɒkjʊpənt/

occupant

乘客
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.
事故发生时，车上有三名乘客。
B2 noun /əˈpoʊ.nənt/

Opponent

对手; 竞争者
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.
象棋选手击败了他最强的对手。
B2 adjective /ˈɔɪl.i/

Oily

油腻的; 油覆盖的; 油滑的
Meaning
covered with oil; containing oil; greasy
Example
Her oily skin needs special care.
她的油腻皮肤需要特别护理。
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。
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。
C1 noun /ˈoʊ.mən/

Omen

未来好运或厄运的征兆
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.
许多人认为一只黑猫横穿你的路是一个坏预兆。
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.
她学习了光学，以了解镜头是如何工作的。
C2 adjective /ˈɔːrnəri/

ornery

脾气暴躁的
Meaning
bad-tempered and combative; stubborn
Example
The ornery old man refused to leave his chair.
那个脾气暴躁的老头拒绝离开他的椅子。
C2 adjective /ɑːlˈfæktəri/

olfactory

Meaning
Relating to the sense of smell.
Example
The perfume activated her olfactory nerves immediately.
A1 noun/adjective/adverb /ˌaʊtˈsaɪd/

outside

外面
Meaning
the external part or surface of something; beyond the boundary
Example
Children were playing outside in the yard.
孩子们在院子外面玩。
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 ˈɔːr.kɪ.streɪt

orchestrate

协调
Meaning
To plan or coordinate the elements of (a situation) to produce a desired effect, especially surreptitiously.
Example
He skillfully orchestrated the entire event.
他巧妙地策划了整个活动。
C1 noun /ˈɒstrəsɪzəm/

ostracism

排斥
Meaning
The act of excluding someone from a group or society.
Example
The student faced ostracism after breaking the rules.
学生在违反规则后遭受了排斥。
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 /ˈoʊ.kən/

oaken

由橡木制成
Meaning
made of or resembling oak wood
Example
The villagers gathered around the oaken table in the hall.
村民们围着大厅里的橡木桌子聚集在一起。
B2 noun /əˌrɪʒ.əˈnæl.ə.ti/

Originality

原创性
Meaning
the quality of being novel or unusual; the ability to think independently and creatively
Example
The artist's work showed great originality and creativity.
艺术家的作品展示了极大的原创性和创造力。
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。
A2 noun /ˈʌn.jən/

Onion

洋葱
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.
我需要切一些洋葱来做咖喱菜谱。
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。
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.
海洋覆盖了地球表面超过70%。