omnipotence
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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。
C1 noun /ˈɒktɪv/

octave

Meaning
A series of eight musical notes, or the interval between one musical pitch and another with double its frequency.
Example
The singer's voice could easily reach the higher octave.
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 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。
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。
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。
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。
C1 noun/verb /ˈoʊvərˌhæŋ/

overhang

悬垂
Meaning
To extend outward and hang over something; a projecting part.
Example
The roof overhang provides shade in the summer.
屋顶的悬垂部分在夏天提供阴凉。
B2 noun /oʊk/

oak

橡树
Meaning
a large tree that produces acorns and has strong, hard wood
Example
The old oak tree provided shade for the entire yard.
那棵老橡树为整个院子提供了阴凉。
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。
B1 noun ˌɔː.ɡən.aɪˈzeɪ.ʃənz

organizations

组织
Meaning
Organized groups of people with a particular purpose
Example
Organizations play a key role in policymaking.
组织在政策制定中发挥着重要作用。
A2 adverb /ˈɒbviəsli/

obviously

显然
Meaning
in a way that is easily perceived or understood; clearly
Example
Obviously, he didn’t read the instructions.
显然，他没有读说明书。
B2 verb /ˌoʊvərˈkʌm/

overcome

克服
Meaning
To succeed in dealing with a problem or difficulty.
Example
You can overcome procrastination with planning.
你可以通过计划来克服拖延症。
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。
B2 verb /ˌoʊvərˈlʊk/

overlook

忽略
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.
当你赶时间时，很容易忽略小细节。
C2 verb /ˈɑːskjʊleɪt/

osculate

亲吻
Meaning
To kiss.
Example
They osculated under the mistletoe during the party.
他们在派对上在槲寄生下接吻。
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%。
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。
C1 adverb /ˈaʊtwədli/

Outwardly

表面上; 外观上;
Meaning
on the surface; externally; in appearance
Example
Outwardly, he seemed calm, but inside he was nervous.
表面上，他看起来很冷静，但内心却很紧张。
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。
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 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。
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。
A2 adjective /ˈɒb.vi.əs/

Obvious

显而易见的; 容易理解的
Meaning
easily perceived or understood; clear and apparent to the mind
Example
It was obvious that she was upset about something.
很明显，她因某事而不高兴。
C1 verb /ˌoʊvərˈʃædoʊ/

overshadow

掩盖
Meaning
to appear more important or significant than something else, reducing its impact
Example
The scandal overshadowed his achievements.
丑闻掩盖了他的成就。
C1 noun /ˈəʊ.nəs/

onus

责任
Meaning
A duty or responsibility, especially a heavy one.
Example
The onus is on the government to provide relief to the victims.
政府有责任向受害者提供援助。
C1 noun /oʊˈeɪ.sɪs/

Oasis

绿洲
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.
旅行者在沙漠中几天后找到了一个绿洲。
B2 noun /ˈɔːrnəmənt/

ornament

装饰品
Meaning
A decorative object that adds beauty to something.
Example
The Christmas tree was decorated with colorful ornaments.
圣诞树上装饰着五颜六色的装饰品。
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。
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。
C1 noun /ˈoʊvərˌtoʊn/

overtone

微妙的含义
Meaning
A subtle quality, implication, or additional meaning beyond the obvious.
Example
His speech had political overtones that were hard to ignore.
他的演讲具有政治性含义，难以忽视。
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！
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。
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。
C2 noun ˌɒbfəsˈkeɪʃən

obfuscation

混淆, 迷惑
Meaning
The action of making something obscure, unclear, or unintelligible.
Example
The obfuscation of the data made it difficult to interpret.
数据的混淆使得它们难以解释。
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。
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。
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.
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。
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。
C2 verb /ˈɑːbvieɪt/

obviate

消除
Meaning
To remove a need or difficulty; to prevent or avoid something.
Example
This new system obviates the need for manual data entry.
这个新系统消除了手动输入数据的需要。
C1 adjective əʊˈpeɪk

opaque

不透明, 难以理解
Meaning
Not able to be seen through; not transparent; difficult to understand.
Example
The glass was too opaque to see through.
玻璃太不透明，无法看透。
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。
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 /ɔːr/

Oar

桨
Meaning
a long pole with a flat blade used to row a boat
Example
He dipped the oar into the water and pulled the boat forward.
他将桨浸入水中并拉动船向前。
C1 verb /ˈoʊvərˌhɔːl/

overhaul

全面改革
Meaning
to examine thoroughly and repair or improve something that is worn or ineffective
Example
The company decided to overhaul its outdated computer system.
公司决定彻底改革其过时的计算机系统。
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。
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。
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.
C1 adjective /əbˈsɛsɪv/

obsessive

强迫症的
Meaning
Relating to or characterized by an obsession; thinking about something too much.
Example
He has an obsessive interest in cleanliness.
他对清洁有强迫症的兴趣。
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 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。
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。
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 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 verb /əbˈteɪn/

obtain

获得
Meaning
to get or acquire something
Example
You need to obtain a visa before traveling abroad.
你需要在出国前获得签证。
B1 verb /oʊ/

owe

欠债
Meaning
to be under obligation to pay or repay; to be indebted
Example
I owe my success to my parents' support.
我将我的成功归功于父母的支持。
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！
A2 pronoun /aʊərˈsɛlvz/

ourselves

我们自己
Meaning
used by the speaker to refer to themselves and one or more others as the object of the verb
Example
We should help ourselves before helping others.
我们应该在帮助他人之前先帮助自己。
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。
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。
B1 verb /ˈɔːrɡənaɪz/

organize

组织
Meaning
to arrange systematically; to plan and coordinate
Example
She organized a surprise party for her friend.
她为她的朋友组织了一个惊喜派对。
C1 noun /ˈɒf.sprɪŋ/

offspring

后代
Meaning
a person's child or children; an animal's young
Example
The bird carefully fed its offspring.
那只鸟小心地喂养了它的后代。
C1 noun /ˈaʊtˌɡroʊθ/

outgrowth

衍生物
Meaning
something that grows out of something else; a natural development or result
Example
The new policy was an outgrowth of years of debate.
新政策是多年辩论的衍生物。
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。
B2 noun /ˈɒt.ər/

Otter

水獺
Meaning
a mammal with webbed feet that lives near water and feeds on fish
Example
The playful otter swam gracefully in the river.
顽皮的水獺优雅地在河里游泳。
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。
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 /ˈaʊtˌskɜːrt/

outskirt

城市郊区
Meaning
the outer edge or border of a town or city
Example
They built a new factory on the outskirts of the city.
他们在城市郊区建了一家新工厂。
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 /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 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。
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 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。
C1 verb /ˈɒfsɛt/

offset

抵消
Meaning
To counterbalance or compensate for something.
Example
The company's losses were offset by gains in other departments.
公司的亏损通过其他部门的收益得到了弥补。
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 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。
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。
C2 noun /ˈɒbsɪkwiːz/

obsequies

葬礼仪式
Meaning
Funeral rites or ceremonies.
Example
The obsequies for the late leader drew thousands of mourners.
已故领导人的葬礼吸引了成千上万的哀悼者。
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。
C1 adjective /ˌoʊvərˈbloʊn/

overblown

夸张
Meaning
excessively exaggerated or inflated
Example
The controversy was overblown by the media.
媒体过度夸大了争议。
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。
A2 adverb; noun /ˌaʊtˈdɔːrz/

outdoors

在户外
Meaning
outside a building; the natural environment outside
Example
We spent the whole afternoon outdoors enjoying the fresh air.
我们整个下午都在户外享受新鲜空气。
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。
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。
B1 adverb /əˈrɪdʒɪnəli/

originally

最初
Meaning
in the beginning, at first
Example
Originally, she wanted to be a doctor.
最初，她想成为一名医生。
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 /ˈɔːfəl/

offal

内脏
Meaning
the internal organs and entrails of an animal used as food; waste parts
Example
The butcher prepared sausages using pork offal.
屠夫使用猪的内脏做香肠。
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。
C1 adjective /əˈkʌlt/

occult

奥秘的
Meaning
Relating to mysterious, supernatural, or magical powers and practices.
Example
She had always been fascinated by the occult and its hidden knowledge.
她一直对奥科尔特及其隐藏的知识感到着迷。
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。
C1 noun /əbˈzɜːvəns/

observance

遵守
Meaning
The practice of following a custom, rule, or religious law.
Example
The festival is held in observance of a centuries-old tradition.
该节庆是为了遵守一项百年传统而举行的。
C2 noun /oʊˈbleɪʃən/

oblation

献祭
Meaning
a religious offering, especially of bread or wine to God
Example
The priest placed the oblation on the altar during the ceremony.
祭司在仪式中将献祭放在祭坛上。
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。
B2 noun /ˌɑb.zɚˈveɪ.ʃən/

Observation

观察
Meaning
the action of watching something carefully; a comment or remark
Example
The scientist made careful observations of the experiment.
科学家仔细观察了实验。
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。
C1 adjective /ˈaʊt.kɑːst/

Outcast

被排斥的人
Meaning
rejected by society; excluded person
Example
He felt like an outcast in his new school.
他在新学校里感觉自己像一个被排斥的人。
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。
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。
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。
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。
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 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。
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 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 /əˈfen.dər/

Offender

罪犯; 违法者
Meaning
a person who commits an illegal act; someone who breaks the law
Example
The young offender was sentenced to community service.
那个年轻的罪犯被判社区服务。
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。
B2 noun /ˈɔr.fən.ɪʒ/

Orphanage

孤儿院
Meaning
an institution for the care and education of children who have lost their parents
Example
The charity built a new orphanage for homeless children.
慈善机构为无家可归的孩子建了一个新孤儿院。
C2 adjective /ˈoʊ.pən ˈhæn.dɪd/

Open-handed

慷慨的; 自由的
Meaning
Generous; liberal; giving freely;
Example
He is very open-handed with his money and always helps those in need.
他对自己的钱非常慷慨，总是帮助有需要的人。
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。
C2 noun /ˌɔːrnɪˈθɑːlədʒi/

ornithology

鸟类学
Meaning
the scientific study of birds
Example
She pursued ornithology to understand the migration patterns of birds.
她追求鸟类学以了解鸟类的迁徙模式。
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。
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 adjective /oʊˈvɜːrt/

overt

公开的
Meaning
Done or shown openly; not hidden or secret.
Example
There was an overt display of hostility between the rivals.
在对手之间有一种公开的敌意表现。
C1 noun /ɒpˈtɒmɪtrɪst/

optometrist

眼科验光师
Meaning
A healthcare professional who examines eyes and prescribes corrective lenses.
Example
The optometrist prescribed new glasses for her.
眼科验光师为她开了新的眼镜。
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 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。
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 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 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。
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。