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A1 noun/adjective/adverb /ˌaʊtˈsaɪd/

outside

外面
Meaning
the external part or surface of something; beyond the boundary
Example
Children were playing outside in the yard.
孩子们在院子外面玩。
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。
B2 adjective /ˈɒp.ʃən.əl/

Optional

可选的
Meaning
not compulsory; left to choice
Example
Wearing a tie is optional for this event.
穿领带是这个活动的可选项。
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 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。
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.
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 /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。
B2 adverb /ˈaʊtraɪt/

Outright

直接; 完全; 毫不保留
Meaning
completely; directly; without reservation or concealment
Example
She rejected the proposal outright.
她直接拒绝了那个提案。
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 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。
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 adjective /ˌaʊtˈlændɪʃ/

outlandish

奇异
Meaning
Looking or sounding bizarre or unfamiliar; strange.
Example
He wore an outlandish costume to the festival.
他穿着一件奇异的服装参加了节日。
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 /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 verb /əbˈtruːd/

obtrude

强行介入
Meaning
to force oneself or one's ideas into a situation uninvited or inappropriately
Example
He didn’t want to obtrude into their private conversation.
他不想打扰他们的私人对话。
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 /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 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。
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 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 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 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 /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。
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。
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。
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 /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。
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。
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。
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 /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 /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。
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。
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。
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。
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。
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。
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。
C1 adjective /ˌɑːpərˈtuːn/

opportune

合适的时刻
Meaning
Happening at a suitable or convenient time.
Example
She arrived at an opportune moment to help.
她在合适的时刻到达，准备帮助。
B2 adjective; verb (past participle) /ˈɒkjʊpaɪd/

occupied

被占用的；被占领的
Meaning
being in use or taken; filled or lived in; controlled or held by force
Example
The room is occupied, so please wait outside.
房间被占用，请在外面等候。
B2 noun /əˈpoʊ.nənt/

Opponent

对手; 竞争者
Meaning
a person who disagrees with or resists a proposal or practice; someone who competes against another
Example
The chess player defeated his strongest opponent.
象棋选手击败了他最强的对手。
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 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。
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 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 noun /əˈprəʊ.bri.əm/

opprobrium

耻辱, 侮辱
Meaning
Harsh criticism or public disgrace.
Example
The scandal brought opprobrium on the politician.
丑闻给政治家带来了耻辱。
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。
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。
B1 adjective /ˈɔːɡənaɪzd/

organized

有条理的
Meaning
Arranged in a systematic way, especially on a large scale.
Example
An organized approach to work increases productivity and reduces stress.
有条理的工作方法可以提高生产力并减少压力。
C2 adjective /ˌoʊvərˈwiːnɪŋ/

overweening

过度自负
Meaning
excessively arrogant or prideful
Example
His overweening pride cost him many friends.
他过度的自豪让他失去了许多朋友。
A1 adjective /əʊˈkeɪ/

okay

没问题
Meaning
used to express agreement or acceptance
Example
It's okay to leave early today.
今天早些离开没问题。
C1 noun /ˈɒptɪks/

optics

光学
Meaning
The branch of physics dealing with light and vision.
Example
She studied optics to understand how lenses work.
她学习了光学，以了解镜头是如何工作的。
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 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。
C1 adjective /əˈblaɪdʒɪŋ/

obliging

乐于助人
Meaning
Willing to help or do favors; accommodating.
Example
The staff at the hotel were very obliging and friendly.
酒店的工作人员非常乐于助人且友好。
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。
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 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。
C1 noun /oʊθ/

Oath

誓言
Meaning
a solemn promise or declaration; a sworn statement
Example
The doctor took an oath to help patients.
医生宣誓帮助病人。
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。
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。
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 /oʊˈbeɪsəns/

obeisance

敬礼
Meaning
A gesture of respect such as a bow or curtsy.
Example
They bowed in obeisance to the king.
他们向国王行了敬礼。
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。
C1 noun /ˈɔːrdɪnəns/

ordinance

法令
Meaning
An authoritative rule, law, or decree issued by a city, town, or authority.
Example
The city council passed an ordinance banning smoking in public parks.
市议会通过了一项法令，禁止在公共公园内吸烟。
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。
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。
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 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 /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。
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。
B2 verb /ˌoʊvərˈsiː/

oversee

监督
Meaning
to supervise or watch over something; to manage and direct
Example
The manager will oversee the entire construction project.
经理将监督整个建筑项目。
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 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。
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。
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。
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 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。
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。
C2 noun /ˌɒn.əˌmæt.əˈpiː.ə/

onomatopoeia

拟声词
Meaning
The formation of a word from a sound associated with what is named.
Example
The word 'buzz' is an example of onomatopoeia.
‘buzz’ 这个词是拟声词的一个例子。
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。
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 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 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。
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。
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。
B2 adverb /ˈɒdli/

oddly

奇怪地
Meaning
in a strange or unusual way; unexpectedly
Example
Oddly, he didn’t seem upset by the bad news.
奇怪的是，他似乎并没有因为坏消息而难过。
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。
C2 verb /ˈoʊɡəl/

ogle

色迷迷地看
Meaning
To look at someone with obvious sexual interest.
Example
He kept ogling the models on the runway.
他一直盯着跑道上的模特看。
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。
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 /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 /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 adjective /ˌoʊvərˈbɛrɪŋ/

overbearing

专横
Meaning
unpleasantly or arrogantly domineering
Example
His overbearing attitude made everyone uncomfortable.
他的专横态度让所有人都感到不舒服。
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 noun ˈəʊnəʃɪp

ownership

所有权
Meaning
The act, state, or right of possessing something; legal title to something.
Example
Ownership of resources was crucial.
资源的所有权至关重要。
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。
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。
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。
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。
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 /ˈɔːrdʒi/

orgy

荒淫派对
Meaning
A wild party involving excessive indulgence, especially of a sexual nature.
Example
The novel described a scandalous orgy in a wealthy mansion.
小说描述了在一座富裕的豪宅里举行的丑闻般的荒淫派对。
C1 noun əˈblɪv.i.ən

oblivion

遗忘, 灭绝, 消失
Meaning
The state of being unaware or unconscious of what is happening; complete forgetfulness.
Example
His name faded into oblivion over time.
随着时间的推移，他的名字渐渐消失在遗忘中。
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 /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。
C2 noun /ˈoʊvərlɔːrd/

overlord

领主
Meaning
A ruler, master, or person of great power and authority over others.
Example
The peasants were forced to pay taxes to their overlord.
农民被迫向他们的领主交税。
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 /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。
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 /ˈaʊtɪŋ/

outing

短途旅行
Meaning
a short trip or excursion, often for leisure or enjoyment
Example
They had a lovely outing at the beach last weekend.
他们上周末在海滩上度过了一个美好的短途旅行。
A1 verb, adjective /oʊn/

own

拥有
Meaning
to possess something; belonging to oneself
Example
She owns a beautiful house in the city.
她拥有一座漂亮的房子。
C1 adjective /ˌɒbsəˈliːt/

obsolete

过时的
Meaning
No longer in use or out of date.
Example
Floppy disks are now completely obsolete.
软盘现在完全过时了。
C2 verb /ˌoʊvərˈstraɪd/

overstride

跨越大步走
Meaning
To stride over something; to step across with long steps.
Example
He managed to overstride the narrow stream with ease.
他轻松地跨越了狭窄的溪流。
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。
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。
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 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。
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。
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。
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。