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B1 adjective /əˈrɪdʒ.ɪ.nəl/

Original

原始的; 主要的; 真实的
Meaning
first; fundamental; primary; authentic
Example
This is the original document, not a copy.
这是原始文件，不是副本。
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 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。
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。
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。
C1 adjective /ˈɔːrθədɑːks/

orthodox

Meaning
conforming to traditional beliefs or practices
Example
He comes from a very orthodox family.
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。
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。
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。
B2 noun /ˈɒfərɪŋ/

offering

提供
Meaning
something that is given, especially as a gift or contribution
Example
The company’s latest offering is an eco-friendly car.
公司的最新产品是一款环保汽车。
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 /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。
A1 pronoun /ˈʌðərz/

others

其他
Meaning
people or things distinct from the ones already mentioned or known
Example
I like to spend time with others.
我喜欢和其他人一起度过时间。
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 /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。
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。
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 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 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。
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。
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 /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。
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 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 verb /əbˈsɛs/

obsess

Meaning
To preoccupy or fill the mind of someone continually and to an excessive degree.
Example
She tends to obsess over small details.
B1 noun /ˌɑk.jəˈpeɪ.ʃən/

Occupation

职业; 工作; 占领
Meaning
a job or profession; the action of taking control of a place
Example
Teaching is her chosen occupation.
教学是她选择的职业。
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。
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。
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。
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。
C2 noun /ˈɒfərtɔːri/

offertory

奉献
Meaning
The part of a religious service when offerings are collected; the offering itself.
Example
The offertory was taken during the Sunday service.
奉献在星期日的礼拜期间收集。
B2 verb əbˈzɜːrvd

observed

庆祝
Meaning
To celebrate or keep a religious or other festival.
Example
The day is observed annually to raise awareness.
这一天每年庆祝，以提高意识。
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。
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 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 /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。
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。
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。
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 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。
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 /əˈprɛs.ɪv/

Oppressive

压迫的
Meaning
Harsh and authoritarian; overwhelming; causing distress; tyrannical;
Example
The oppressive heat made it difficult to work outside during the summer.
压迫性的热浪使得夏天在外工作变得很困难。
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。
C2 verb ˈɑːb.fə.skeɪt

obfuscate

使模糊，掩盖，混淆
Meaning
Render obscure, unclear, or unintelligible.
Example
Politicians often obfuscate facts to mislead people.
政客们经常使事实变得模糊，以误导人民。
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 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。
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。
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 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 /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 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.
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 adjective ˈɒptɪmaɪzd

optimized

优化, 改善, 更有效
Meaning
Made as fully perfect, functional, or effective as possible; improved to achieve maximum efficiency.
Example
The system has been optimized for faster performance.
系统已经针对更快的性能进行了优化。
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。
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。
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。
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 /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 /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。
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 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。
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 /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。
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。
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。
C1 adjective /ˈɒptɪməm/

optimum

最优
Meaning
Most conducive to a favorable outcome; best.
Example
To achieve optimum results, we need to improve efficiency.
为了获得最佳结果，我们需要提高效率。
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。
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。
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。
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。
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 /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。
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。
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 /əˈblɪkwɪti/

obliquity

歪曲
Meaning
Deviation from moral or usual conduct; indirectness or lack of straightforwardness.
Example
The politician was criticized for the obliquity of his answers.
那位政治家因其回答的歪曲性而受到批评。
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。
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。
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。
C1 adjective /ˈɒm.ɪ.nəs/

Ominous

不祥的; 威胁的
Meaning
giving the impression that something bad will happen; threatening; foreboding
Example
The dark clouds looked ominous before the storm.
暴风雨前，黑云看起来预示着灾难。
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。
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。
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 /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。
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。
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。
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。
C1 noun /oʊˈbɪt.ʃu.er.i/

Obituary

讣告
Meaning
a notice of someone's death published in a newspaper; biographical account of deceased person
Example
The newspaper published his obituary yesterday.
报纸昨天发布了他的讣告。
C2 noun /ˈɑb.lə.kwi/

Obloquy

严厉的批评或言语侮辱；公开谴责
Meaning
harsh criticism or verbal abuse; strong public condemnation
Example
The politician faced obloquy after the scandal.
政治家在丑闻之后遭遇了严厉的批评。
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。
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。
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。
B2 noun /əˈfens/

Offence

罪行; 侵犯法规
Meaning
a breach of law or rule; an annoyance or resentment
Example
Stealing is a serious offence punishable by law.
盗窃是严重的罪行，依法可追究。
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。
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 /ˌɒbstəˈtrɪʃən/

obstetrician

产科医生
Meaning
A doctor specializing in pregnancy, childbirth, and women's reproductive health.
Example
The obstetrician monitored the mother’s health throughout the pregnancy.
产科医生在整个怀孕过程中监测了母亲的健康。
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 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。
B2 noun /ˈaʊt.laɪn/

Outline

大纲; 轮廓; 摘要
Meaning
a general description or plan showing the essential features of something; the main points
Example
The teacher provided an outline of the course syllabus.
老师提供了课程大纲。
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 /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。
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。
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。
B2 verb /ˌoʊvərˈteɪk/

overtake

超过
Meaning
to catch up with and pass someone or something; to surpass
Example
The runner managed to overtake his competitor in the final lap.
跑步者在最后一圈超过了他的竞争对手。
B2 verb /ˈɒkjʊpaɪ/

occupy

占据
Meaning
to take up space or time; to live or work in a place
Example
The new family will occupy the house next month.
新家庭将于下个月入住这所房子。
B1 adjective, adverb /ˈoʊvərɔːl/

overall

总体上
Meaning
in general or as a whole
Example
Overall, the project has been successful.
总体上，项目已成功。
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 /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。
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 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 /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 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。
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。
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 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 /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。
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 /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 /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 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。
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。