overture
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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。
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 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。
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.
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The process of becoming obsolete or outdated and no longer used.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 /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。
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。
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 /aʊtˈmoʊdɪd/

outmoded

过时的
Meaning
No longer in fashion or useful; outdated.
Example
That old computer is completely outmoded.
那台旧电脑完全过时了。
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。
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 /ˈɒm.lət/

Omelet

煎蛋饼
Meaning
a dish made from beaten eggs cooked in a frying pan and often folded around a filling
Example
She made a cheese omelet for breakfast.
她做了一个奶酪煎蛋饼作为早餐。
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。
B2 adjective /ˈɒnɡəʊɪŋ/

ongoing

进行中
Meaning
continuing; still in progress
Example
The ongoing project will finish next month.
进行中的项目将在下个月完成。
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 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。
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。
C2 verb /ˌoʊvərˈliːp/

overleap

跳过
Meaning
To jump over something; to omit or disregard something.
Example
He managed to overleap the fence easily.
他轻松地越过了栅栏。
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 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。
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 /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。
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 adverb /ˈoʊpənli/

Openly

公开地; 公共地
Meaning
in a frank and honest way; without concealment; publicly
Example
She spoke openly about her struggles with mental health.
她公开谈论了自己在心理健康方面的困难。
B2 noun /ˈoʊ.dər/

Odour

气味
Meaning
a distinctive smell, especially an unpleasant one
Example
The odour of fresh bread filled the kitchen.
新鲜面包的气味充满了厨房。
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。
C2 adjective /əbˈsiːkwɪəs/

obsequious

奉承
Meaning
Excessively obedient or attentive in a servile way.
Example
The waiter gave an obsequious bow to every customer.
服务员对每个顾客鞠了一躬。
A2 noun əˈlɪm.pɪk ɡeɪmz

Olympic Games

奥林匹克运动会
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.
奥林匹克运动会汇聚了世界上最顶尖的运动员。
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。
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 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。
B2 adjective /ˌɔːɡənaɪˈzeɪʃənəl/

organizational

组织性的
Meaning
relating to the structure or arrangement of a company or group
Example
He works on improving the organizational structure of the company.
他在改善公司的组织结构方面工作。
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。
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。
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。
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。
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 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 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。
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。
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。
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。
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。
A1 preposition /ɒn/

on

在
Meaning
physically in contact with and supported by a surface
Example
The book is on the table.
书在桌子上。
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 noun ˈaʊt.sɔːr.sɪŋ

outsourcing

外包
Meaning
The practice of having certain job functions done outside a company instead of having an in-house department or employee handle them.
Example
Many companies use outsourcing to reduce labor costs.
许多公司使用外包来降低劳动力成本。
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。
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。
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。
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。
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 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 noun (plural) /ˈɔːrdʒiːz/

orgies

狂欢
Meaning
Wild gatherings involving excessive indulgence in food, drink, or sexual activity.
Example
The ancient Romans were infamous for their lavish feasts and orgies.
古罗马人以其奢华的宴会和狂欢而闻名。
C1 adjective /ˌɔːrθəˈpiːdɪk/

orthopedic

与骨骼或肌肉畸形的矫正有关
Meaning
Relating to the correction of deformities of bones or muscles.
Example
She visited an orthopedic surgeon for her back pain.
她因为背痛去看了骨科医生。
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 /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。
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。
A1 noun /ɒkˈtoʊbər/

october

十月
Meaning
the tenth month of the year in the Gregorian calendar
Example
The weather becomes cooler in October.
十月天气开始变凉。
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 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 adjective, verb /əbˈskjʊr/

obscure

模糊
Meaning
Not clearly expressed or understood; to make something difficult to see or understand.
Example
The meaning of the poem was obscure to most readers.
诗的意义对大多数读者来说是模糊的。
A1 conjunction /ɔːr/

or

或
Meaning
used to link alternatives
Example
You can have tea or coffee.
你可以喝茶或咖啡。
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。
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。
B2 noun oʊˈbiː.sə.t̬i

obesity

肥胖症
Meaning
The condition of being grossly fat or overweight.
Example
Obesity increases the risk of diabetes and heart disease.
肥胖症增加糖尿病和心脏病的风险。
C1 noun /ˈaʊtriːtʃ/

outreach

援助扩展
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.
慈善机构为无家可归的人推出了一个新的援助扩展计划。
B2 noun, verb /ˈaʊtlɔː/

outlaw

Meaning
as a noun: a person who breaks the law and lives outside its protection; as a verb: to make something illegal
Example
The government decided to outlaw the harmful practice.
B2 adjective /aʊtˈstændɪŋ/

outstanding

杰出
Meaning
extremely good or impressive; not yet resolved or paid
Example
She received an award for her outstanding performance.
她因出色的表现获得了奖项。
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。
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 /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。
C1 adjective /əˈbliːk/

Oblique

倾斜; 对角线; 间接或回避
Meaning
slanting; diagonal; indirect or evasive
Example
The artist drew an oblique line across the canvas.
艺术家在画布上画了一条倾斜的线。
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。
A2 noun /ˈɒbdʒɪkt/

object

物体
Meaning
a thing that can be seen and touched
Example
The table is an object in the room.
桌子是房间里的一个物体。
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 /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。
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。
C1 adjective /ˌoʊvərˈrɔt/

overwrought

焦虑 / 过度紧张
Meaning
extremely agitated or nervous; excessively elaborate
Example
She was too overwrought to speak clearly after the accident.
她在事故后太焦虑，无法清楚地讲话。
C1 adjective /əbˈzɜːrvənt/

Observant

观察力强的
Meaning
quick to notice things; watchful; attentive
Example
The observant detective noticed every small detail at the crime scene.
观察力强的侦探注意到了犯罪现场的每个细节。
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 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 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。
C2 adjective /ˌɒbsəˈlɛsnt/

obsolescent

过时的
Meaning
Becoming outdated or on the way to becoming obsolete.
Example
The obsolescent technology could not compete with modern devices.
过时的技术无法与现代设备竞争。
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。
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 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 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 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 /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。
B2 noun /wʌn θɜːd/

one-third

三分之一
Meaning
one part of something that is divided into three equal parts
Example
One-third of the class was absent today.
班级的三分之一今天缺席。
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 /ˈaʊtbɜːrst/

outburst

情感或活动的突然爆发
Meaning
a sudden release of strong emotion or activity
Example
She had an angry outburst during the meeting.
她在会议期间突然发火。
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。
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。
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 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。
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 /ˌoʊvərˈiːt/

overeat

幸福
Meaning
To eat more food than the body needs.
Example
She tends to overeat when she is stressed.
她在收到奖项时无法掩饰自己的幸福。
C1 noun /ˈɒktəɡən/

octagon

八边形
Meaning
A polygon with eight sides and eight angles.
Example
The stop sign is shaped like an octagon.
停车标志呈八边形。
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。
C1 verb /aʊst/

oust

驱逐
Meaning
To remove someone from a position or place of power or authority.
Example
The rebels ousted the dictator from power.
叛乱者将独裁者赶下台。
C2 noun /ˈaʊtˌrɪɡər/

outrigger

稳定结构
Meaning
a projecting structure on a boat, used for stability, or a boat fitted with such support
Example
The fisherman paddled his outrigger canoe across the lagoon.
渔民划着带有支撑的独木舟穿过泻湖。
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 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。
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 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。
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 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 /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。
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。
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。
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 /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。
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。
B1 adjective /əˈkeɪ.ʒən.əl/

Occasional

偶然的
Meaning
occurring infrequently or irregularly; happening from time to time
Example
She enjoys occasional walks in the park.
她喜欢在公园里偶尔散步。
C2 noun /ˈoʊ.kəm/

oakum

旧绳纤维
Meaning
loose fibers obtained by untwisting old ropes, used for caulking ships
Example
The shipbuilders used oakum to seal the gaps in the wooden planks.
造船工人使用欧卡姆来密封木板之间的缝隙。
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。
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 /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。
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。