Out-sider
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B2 noun /ˈaʊt.saɪ.dər/

Out-sider

局外人
Meaning
a person who does not belong to a particular group; someone not accepted by a group
Example
As an outsider, he found it difficult to understand their traditions.
作为外人，他发现很难理解他们的传统。
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。
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。
C2 noun /ˌoʊpəˈlɛsəns/

opalescence

欧泊光泽
Meaning
a milky or pearly appearance of a surface like that of an opal
Example
The pearl had a gentle opalescence under the light.
珍珠在光下有一种柔和的欧泊光泽。
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。
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。
B2 verb /ˌoʊvərˈloʊd/

overload

过载
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.
不要过载洗衣机，否则它可能会坏掉。
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。
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。
B2 noun /ˈaʊtˌfɪt/

outfit

服装
Meaning
A set of clothes worn together, often for a particular occasion.
Example
She wore a beautiful outfit to the party.
她穿了一套漂亮的服装去参加派对。
C1 adjective /əˈblɪɡ.ə.tɔː.ri/

obligatory

强制的
Meaning
Required by a legal, moral, or other rule; compulsory.
Example
Wearing a seatbelt is obligatory in most countries.
在大多数国家，系安全带是强制的。
B1 adverb /əˈkeɪʒənəli/

Occasionally

偶尔; 有时;
Meaning
sometimes; from time to time; not regularly
Example
I occasionally visit my grandmother on weekends.
我偶尔在周末去看望我的祖母。
C1 adjective /ˈɑp.ər.ə.tɪv/

Operative

有效的; 运行中的; 工作中的; 操作性的;
Meaning
Functioning; in effect; working; active;
Example
The new safety protocols became operative immediately after the accident.
新的安全协议在事故发生后立即生效。
C1 adjective /ˈəʊnərəs/

onerous

繁重
Meaning
involving a great deal of effort, difficulty, or burden
Example
Fulfilling the contract proved to be an onerous task for the company.
履行合同对公司来说是一项繁重的任务。
C2 adjective /ˈɒpjʊlənt/

opulent

奢华的
Meaning
Ostentatiously rich, luxurious, or lavish.
Example
They hosted an opulent wedding with gold decorations.
他们举办了一场奢华的婚礼，装饰有金色装饰品。
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。
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。
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。
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 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。
B1 adjective /ˌoʊvərˈweɪt/

overweight

超重
Meaning
heavier than is considered healthy or normal
Example
The doctor advised him to lose weight as he was overweight.
医生建议他减肥，因为他超重。
C2 adjective /ˌɔːfˈkiː/

off-key

跑调
Meaning
out of tune; not in accordance with expected standards
Example
The singer was slightly off-key during the performance.
歌手在表演时稍微跑调了。
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。
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。
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。
B2 noun /ˌaʊtˈsaɪdə(r)/

outsider

局外人
Meaning
a person who is not accepted as a member of a particular group or community
Example
As a new student, she often felt like an outsider at school.
作为新生，她常常觉得自己在学校是个局外人。
B2 noun /ˌɒpəˈzɪʃən/

opposition

反对
Meaning
the action of opposing or resisting something
Example
The opposition to the new law was strong.
对新法律的反对很强烈。
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。
B2 noun /ˈaʊtˌbreɪk/

outbreak

爆发
Meaning
a sudden start or occurrence of something unpleasant, like disease or violence
Example
There was an outbreak of flu in the city.
城市中爆发了流感。
C2 noun /oʊd/

ode

颂诗
Meaning
a lyrical poem, often expressing praise or strong emotions
Example
The poet wrote an ode to the beauty of nature.
诗人写了一首歌颂自然美的颂诗。
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 /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 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。
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。
A2 noun /ˈoʊpənɪŋ/

opening

开幕
Meaning
an act or instance of beginning something
Example
The opening of the new store was a huge success.
新店的开业是一个巨大的成功。
C2 noun /ˈɒrɪz(ə)n/

orison

祷告
Meaning
a prayer, especially a devout or formal one
Example
He whispered a quiet orison before going to sleep.
他在睡觉前低声祈祷。
C1 verb /ˈɔːstrəˌsaɪz/

ostracize

排斥
Meaning
to exclude someone from a group or society; to banish or shun
Example
After the scandal, he was ostracized by his former colleagues.
丑闻发生后，他被前同事排斥。
C1 noun /ˈoʊvərˌtʊr/

overture

序曲 / 提议
Meaning
An introduction to something more substantial; a proposal or preliminary action.
Example
The peace overture was welcomed by both nations.
和平提议得到了两个国家的欢迎。
C1 verb /ɔːrˈdeɪn/

ordain

Meaning
To officially make someone a priest or minister; to decree or order something officially.
Example
The bishop will ordain three new priests this Sunday.
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 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。
A2 noun /ˈʌv.ən/

Oven

烤箱
Meaning
an enclosed compartment used for heating, baking, or drying food
Example
She baked cookies in the oven for thirty minutes.
她在烤箱里烤了三十分钟的饼干。
C2 adjective /ˈoʊdiəs/

odious

可憎的
Meaning
extremely unpleasant or repulsive
Example
The dictator was remembered for his odious crimes.
这位独裁者因他可憎的罪行而被记住。
A1 pronoun /aʊərz/

ours

我们的
Meaning
belonging to or associated with us
Example
This victory is ours.
这个胜利是我们的。
C1 noun /ˌoʊvərprəˈdʌkʃən/

overproduction

过度生产
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.
经济危机是由商品的过度生产引起的。
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 verb /ˌaʊtˈweɪ/

outweigh

比...更重要
Meaning
To be more important, valuable, or significant than something else.
Example
The benefits of the new policy outweigh the risks.
新政策的好处超过了风险。
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。
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。
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。
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 adjective ˈɒb.stɪ.nət

obstinate

固执
Meaning
Refusing to change one's mind or accept others' advice easily.
Example
He remained obstinate despite the logical arguments.
尽管有逻辑上的辩论，他依然固执。
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 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。
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。
C1 noun /ˈɔːr.ə.tɔːr.i/

oratory

演讲艺术
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.
他出色的演讲技巧使他赢得了辩论比赛。
C1 noun ˌɒp.tɪ.maɪˈzeɪ.ʃən

optimization

优化
Meaning
Improving processes to increase performance and efficiency.
Example
SEO optimization helps websites rank higher on search engines.
SEO优化帮助网站在搜索引擎中排名更高。
A1 pronoun, noun, adjective /wʌn/

one

一
Meaning
the number equivalent to the sum of zero and one; a single person or thing
Example
Only one student answered the question.
只有一个学生回答了问题。
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。
A2 noun /əˈlɪmpɪks/

olympics

奥林匹克运动会
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.
奥林匹克运动会将全世界的运动员聚集在一起。
C2 noun ˈɒpjʊləns

opulence

奢华
Meaning
Great wealth or luxuriousness.
Example
The opulence of the mansion was evident in its ornate furnishings.
大厦的奢华体现在其华丽的家具中。
C2 noun /ˌɒstɛnˈteɪʃən/

ostentation

炫耀
Meaning
excessive display of wealth or knowledge intended to attract admiration or envy
Example
The billionaire’s party was full of ostentation and luxury.
亿万富翁的派对充满了炫耀和奢华。
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。
A2 verb /ˈɔːfər/

offer

提供
Meaning
to present something for acceptance or rejection; to propose
Example
She offered to help with the project.
她提出帮助这个项目。
C2 noun /ˈɒb.stɪ.nə.si/

obstinacy

固执
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.
他的固执使谈判变得困难。
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 /ˈɑp.tə.mɪst/

Optimist

乐观主义者
Meaning
a person who tends to be hopeful and confident about the future; someone who sees the good side of things
Example
As an optimist, she always believed things would improve.
作为乐观主义者，她一直相信事情会变得更好。
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。
B1 noun ˌɒpəˈtjuːnɪtiz

opportunities

机会
Meaning
A set of circumstances that makes it possible to do something; chances for advancement or success.
Example
Opportunities for jobs decreased.
工作的机会减少了。
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。
C1 noun ɔːrˈdiːl

ordeal

艰难的考验
Meaning
A physical or mental painful experience that must be endured
Example
Surviving the wilderness was a tough ordeal for them.
在野外生存对他们来说是一场艰难的考验。
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 /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。
A2 noun /ˈɒpərə/

opera

歌剧
Meaning
a dramatic performance in which the actors sing most of their lines
Example
We watched a beautiful opera at the theater last night.
我们昨晚在剧院观看了一场美丽的歌剧。
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。
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 /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。
C1 adjective /ˌəʊvərˈstɪmjʊˌleɪtɪd/

overstimulated

过度刺激的
Meaning
Excessively excited or aroused, overwhelmed by too much stimulus.
Example
Overstimulated minds can lead to burnout and decreased productivity.
过度刺激的头脑可能导致倦怠和生产力下降。
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。
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。
A1 adjective /oʊˈkeɪ/

ok

好的
Meaning
used to indicate agreement, approval, or understanding
Example
Okay, let's go to the park.
好的，我们去公园。
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 verb /əˈblaɪdʒ/

oblige

迫使
Meaning
to compel or require someone to do something; to help or do a favor
Example
I would be happy to oblige you with the information you need.
我很乐意为你提供所需的信息。
B1 noun ˈɒk.sɪ.dʒən

oxygen

氧气。无色、无味的气体，是生命必不可少的成分。
Meaning
A colorless, odorless reactive gas, the chemical element of atomic number 8 and the life-supporting component of the air.
Example
Oxygen is vital for life.
氧气对生命至关重要。
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。
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。
C1 verb /ˌoʊvərˈriːtʃ/

overreach

过度伸展
Meaning
to go beyond what is proper, acceptable, or achievable; to overextend
Example
The politician overreached by making promises he couldn't keep.
那位政治家在做出无法兑现的承诺时，过度伸展了自己。
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 /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。
C1 noun /ɒpˈtɒmətri/

optometry

验光学
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.
她在大学学习验光学，成为一名眼科专家。
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。
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。
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。
B2 noun /ˈaʊtlʊk/

outlook

前景, 预测
Meaning
a person's general attitude or view; a forecast or prospect
Example
The economic outlook for the year is positive.
今年的经济前景是积极的。
C1 adjective ˈɒk.sɪ.də.tɪv

oxidative

与氧化相关
Meaning
Related to or caused by oxidation, especially cellular damage from free radicals.
Example
Excess stress can lead to oxidative damage in cells.
过度的压力可能导致细胞中的氧化损伤。
B2 noun ˈoʊzoʊn dɪˈpliʃən

ozone depletion

臭氧消耗
Meaning
The reduction in the amount of ozone in the Earth's stratosphere, leading to increased UV radiation.
Example
Ozone depletion increases UV radiation.
臭氧消耗增加了紫外线辐射。
B2 noun /əbˈdʒek.ʃən/

Objection

反对; 异议; 抗议;
Meaning
an expression of disagreement or disapproval; a reason for disagreeing
Example
The lawyer raised an objection during the trial.
律师在审判过程中提出了异议。
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。
B2 adjective /əˈpəʊzd/

opposed

反对的
Meaning
being against or in disagreement with something
Example
She is strongly opposed to animal testing.
她坚决反对动物实验。
B2 noun /ˌɒb.zəˈveɪ.ʃənz/

observations

观察
Meaning
The action or process of observing something carefully.
Example
Observations of distant galaxies provide new insights.
对遥远星系的观察提供了新的见解。
C1 noun /ˈɑd.ɪ.ti/

Oddity

奇异现象
Meaning
something that is strange or unusual; a peculiar trait
Example
His habit of sleeping standing up was considered an oddity.
他站着睡觉的习惯被视为一种奇异现象。
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 /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 noun /ˈɑː.lɪv/

Olive

橄榄
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.
橄榄油被认为是最健康的烹饪油之一。
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。
B2 noun /ɔːrˈɡæn.ɪk ˈfɑːr.mɪŋ/

organic farming

有机农业
Meaning
Farming method that avoids synthetic chemicals and fertilizers, using natural methods instead.
Example
Organic farming improves soil health and reduces pollution.
有机农业改善了土壤健康并减少了污染。
B2 noun /ˈɔɪ.stər/

Oyster

生蚝
Meaning
a type of shellfish that can be eaten and sometimes contains pearls
Example
She ordered fresh oysters at the seafood restaurant.
她在海鲜餐厅点了新鲜的生蚝。
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 /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。
A1 adjective /ˈɔːr.ɪndʒ/

Orange

橙色
Meaning
having a color between red and yellow like that of a ripe orange fruit
Example
The orange sunset painted the sky magnificently.
橙色的日落把天空画得非常壮丽。
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。
A1 verb /ˈoʊpən/

open

打开
Meaning
to move something so as to allow access; to begin
Example
Please open the door for me.
请为我打开门。
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 adjective /ˈoʊ.vɔɪd/

ovoid

卵形
Meaning
egg-shaped; resembling an oval or ellipse
Example
The artist painted an ovoid shape in the center of the canvas.
艺术家在画布中心画了一个卵形的形状。
C1 noun /əbˈstrʌkʃən/

obstruction

障碍
Meaning
Something that blocks or gets in the way; the action of obstructing.
Example
There was an obstruction on the railway track.
铁路上有一个障碍。
B1 adjective /ˈaʊtər/

outer

外部
Meaning
situated on or toward the outside; external
Example
The outer layer of the jacket is waterproof.
夹克的外层是防水的。
C2 noun /ˌɑːbdʒərˈɡeɪʃən/

objurgation

严厉的斥责
Meaning
a harsh scolding or strong rebuke
Example
His misconduct earned him a severe objurgation from the manager.
他的不当行为让他受到了经理的严厉斥责。
C2 noun /ˈɔːrzmən/

Oarsman

划船者
Meaning
a person who rows a boat, especially as a member of a racing crew
Example
The experienced oarsman rowed the boat across the river.
经验丰富的划船者划船过了河。
B1 noun /ˈɒbstəkəlz/

obstacles

障碍
Meaning
Things that block one's way or prevent or hinder progress.
Example
Obstacles in life can often lead to valuable lessons.
生活中的障碍常常导致宝贵的教训。
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 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。