optimization
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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。
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。
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。
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。
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。
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 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。
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。
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。
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。
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。
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。
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。
C2 noun /ɒmˈnɪʃəns/

omniscience

全知
Meaning
the state of knowing everything
Example
The novel's narrator has an air of omniscience, revealing every character's thoughts.
小说的叙述者具有全知的气质，揭示每个角色的想法。
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。
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。
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。
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。
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。
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。
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。
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 /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。
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。
B2 adjective /ˈɔː.də.li/

Orderly

有序的; 系统的; 平静的
Meaning
well-organized; systematic; peaceful
Example
Please keep your desk orderly and clean.
请保持您的桌面整齐和干净。
C1 verb ˈɔː.kɪ.streɪ.tɪd

orchestrated

精心策划
Meaning
Planned or coordinated carefully and deliberately.
Example
The attacks were orchestrated with precision.
袭击被精确地策划了。
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。
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。
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 /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。
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。
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。
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。
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。
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 adjective /ɒˈstɛnsɪv/

ostensive

显性
Meaning
clearly demonstrative or pointing out; explicitly shown
Example
The teacher gave an ostensive example to clarify the concept.
老师举了一个显性的例子来阐明概念。
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。
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。
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。
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 /ɔːˈreɪʃən/

oration

演讲
Meaning
A formal speech, especially one given on a ceremonial occasion
Example
The president delivered an inspiring oration.
总统发表了鼓舞人心的演讲。
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 /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 /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。
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 noun /ˈəʊpəs/

opus

创作作品
Meaning
A creative work, especially a large and important piece of music or art.
Example
The composer considered the symphony his greatest opus.
作曲家认为交响曲是他最大的创作作品。
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。
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 verb /ˌaʊtˈstrɛtʃ/

outstretch

伸展
Meaning
To extend or stretch something outward.
Example
He outstretched his hand to help her up.
他伸出手来帮助她站起来。
C2 adjective /ɑːlˈfæktəri/

olfactory

Meaning
Relating to the sense of smell.
Example
The perfume activated her olfactory nerves immediately.
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 verb /ˈɔːreɪt/

orate

演讲
Meaning
To speak in a formal, often pompous manner
Example
He began to orate at the ceremony.
他在仪式上开始演讲。
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。
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。
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。
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。
B1 noun /əˈkeɪ.ʒən/

Occasion

场合; 特殊事件
Meaning
a particular time or instance of an event; a special celebration
Example
Their wedding was a joyous occasion.
他们的婚礼是一个喜庆的场合。
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 /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。
B2 noun /əˈfɛns/

offense

犯罪
Meaning
an illegal act; a crime
Example
The offense was committed in broad daylight.
这个犯罪是在白天犯下的。
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 /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。
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。
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。
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 /ˌoʊld ˈfæʃənd/

old-fashioned

过时的
Meaning
not modern; belonging to an earlier time
Example
He still wears an old-fashioned hat.
他仍然戴着一顶过时的帽子。
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 /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 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。
B1 noun ˌɔː.ɡən.aɪˈzeɪ.ʃən

organization

组织
Meaning
An organized group of people with a particular purpose, such as a business or government department.
Example
The organization was officially inaugurated in 2024.
该组织于2024年正式启用。
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。
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 /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 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 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。
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。
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。
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。
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。
A1 adverb /aʊt/

out

外面
Meaning
moving or appearing away from the inside or center; not at home or present
Example
He stepped out of the room quietly.
他悄悄地走出房间。
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。
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。
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。
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。
A1 adverb /wʌns/

Once

一次; 过去的某个时候
Meaning
one time only; at some time in the past; formerly
Example
I have been to Paris once in my life.
我一生中只去过一次巴黎。
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 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。
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。
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。
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。
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。
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。
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 /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 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。
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。
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。
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 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。
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。
B2 adverb /ˌoʊvərˈnaɪt/

Overnight

一夜之间; 突然; 非常快速
Meaning
during the night; suddenly; very quickly
Example
The city was transformed overnight.
这座城市一夜之间发生了变化。
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 noun /ˈɑn.set/

Onset

开始; 起始
Meaning
the beginning or early stages of something; the start of a medical condition
Example
The onset of winter brought heavy snowfall.
冬天的开始带来了大雪。
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。
B1 noun /ˌɒp.əˈtjuː.nə.ti/

opportunity

机会
Meaning
A favorable chance or set of circumstances that makes it possible to do something.
Example
She seized the opportunity to study abroad.
她抓住了去国外学习的机会。
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。
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。
C2 verb /əˈkluːd/

occlude

堵塞
Meaning
To block or close up an opening or passage.
Example
The pipe was occluded by mineral deposits.
管道因矿物沉积物而被堵塞。
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 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.
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。
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 /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。
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 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。
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 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。
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。
B1 noun /ˈɑp.ʃən/

Option

选项
Meaning
a thing that is or may be chosen; an alternative course of action
Example
You have the option to work from home or office.
你可以选择在家工作或在办公室工作。
A2 adjective/adverb /ˈɒnˌlaɪn/

online

在线
Meaning
connected to or available through the internet
Example
I prefer shopping online rather than going to stores.
我更喜欢网上购物，而不是去商店。