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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。
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。
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 /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。
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 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。
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 /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.
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 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。
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 /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。
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。
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。
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。
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 verb /ˌoʊvərˈtɜrn/

overturn

推翻 / 取消裁决
Meaning
to turn something upside down or to reverse a decision or judgment
Example
The court decided to overturn the previous ruling.
法院决定推翻先前的裁决。
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。
B1 noun əbˈdʒek.tɪv

objective

目标
Meaning
A thing aimed at or sought; a goal.
Example
The main objective is to test sustainability.
主要目标是测试可持续性。
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。
C2 noun /ˈɑːbəlɪsk/

obelisk

方尖碑
Meaning
A tall, four-sided, narrow tapering monument with a pyramid-shaped top.
Example
The ancient Egyptians built obelisks to honor their gods.
古埃及人建造了方尖碑来纪念他们的神。
C2 adjective /ˌoʊpəˈlɛsənt/

opalescent

欧泊色的
Meaning
showing or reflecting a milky, iridescent light like an opal
Example
The opalescent sky glowed with shades of pink and blue.
欧泊色的天空闪烁着粉色和蓝色的色调。
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 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 verb /aʊtˈwɪt/

outwit

智胜
Meaning
to defeat or gain an advantage over someone by being more clever or cunning
Example
The fox managed to outwit the hunters.
狐狸成功地智胜了猎人。
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。
A2 noun /əˈlɪmpɪks/

olympics

奥林匹克运动会
Meaning
an international sports competition held every four years with athletes from many countries
Example
The Olympics bring athletes from all over the world together.
奥林匹克运动会将全世界的运动员聚集在一起。
C1 noun /ˌɑːk.sɪˈmɔːr.ɒn/

oxymoron

矛盾修饰法
Meaning
a figure of speech where two contradictory terms are combined
Example
The phrase 'deafening silence' is a classic oxymoron.
短语 '震耳欲聋的寂静' 是一个经典的矛盾修饰法。
B2 adjective /ˈɔɪl.i/

Oily

油腻的; 油覆盖的; 油滑的
Meaning
covered with oil; containing oil; greasy
Example
Her oily skin needs special care.
她的油腻皮肤需要特别护理。
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 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 /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。
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 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。
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 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。
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。
B2 verb /əˈblaɪdʒ/

oblige

迫使
Meaning
to compel or require someone to do something; to help or do a favor
Example
I would be happy to oblige you with the information you need.
我很乐意为你提供所需的信息。
B2 noun /ˈaʊtˌfɪt/

outfit

服装
Meaning
A set of clothes worn together, often for a particular occasion.
Example
She wore a beautiful outfit to the party.
她穿了一套漂亮的服装去参加派对。
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。
C2 adjective /əˈfɪʃəs/

officious

多管闲事
Meaning
Excessively eager to offer unwanted help or advice; meddlesome.
Example
The officious guard kept interrupting the visitors with unnecessary instructions.
那位多管闲事的警卫不断用不必要的指令打扰游客。
B2 adjective /ˈɒp.tɪ.məl/

optimal

最优，最适合的
Meaning
Best or most favorable; the most effective under particular conditions.
Example
The optimal temperature for plant growth is around 25°C.
植物生长的最优温度大约是25°C。
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 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。
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。
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。
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。
B2 noun /ˈaʊt.saɪ.dər/

Out-sider

局外人
Meaning
a person who does not belong to a particular group; someone not accepted by a group
Example
As an outsider, he found it difficult to understand their traditions.
作为外人，他发现很难理解他们的传统。
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。
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。
B2 adverb /ˈəʊvəli/

overly

过度
Meaning
to an excessive degree or extent
Example
She was overly concerned about the results.
她对结果过于担忧。
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 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 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。
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。
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。
B1 noun /aʊl/

Owl

猫头鹰
Meaning
a nocturnal bird of prey with large eyes and a hooked beak
Example
The owl hooted softly in the darkness of the forest.
猫头鹰在森林的黑暗中轻轻地叫了。
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 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。
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。
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。
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 /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 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 /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。
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。
C1 adjective /ˈɒptɪk/

optic

光学的
Meaning
Relating to the eye or vision.
Example
The optic nerve carries signals from the eye to the brain.
视神经将信号从眼睛传递到大脑。
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。
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 ˈəʊ.və.hed

overhead

管理费用
Meaning
Ongoing business expenses not directly attributable to creating a product or service.
Example
The company reduced its overhead to increase profits.
公司减少了管理费用以增加利润。
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。
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。
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 noun /ˈɑːdəsi/

odyssey

漫长的旅行
Meaning
a long, adventurous journey; a series of experiences
Example
Her career has been an odyssey of challenges and achievements.
她的职业生涯是一场挑战和成就的漫长旅行。
C1 verb /əˈfɪʃieɪt/

officiate

主持
Meaning
To perform official duties, especially in a ceremony or as a referee.
Example
The priest will officiate the wedding ceremony.
牧师将主持婚礼仪式。
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。
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。
B2 noun/verb /ˌoʊvərˈlæp/

overlap

Meaning
To extend over and cover partly; an area where things coincide.
Example
The two meetings overlap by an hour.
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。
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。
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。
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。
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 /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 adjective /ˈɒkjʊlər/

ocular

眼科的
Meaning
Relating to the eye or vision.
Example
The patient was referred to a specialist for ocular treatment.
患者被转诊到眼科专家进行治疗。
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。
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 ˈoʊʃən əˌsɪdɪfɪˈkeɪʃən

ocean acidification

海洋酸化
Meaning
The ongoing decrease in the pH of the Earth's oceans, caused by the absorption of carbon dioxide from the atmosphere.
Example
Ocean acidification is caused by atmospheric CO2 absorption.
海洋酸化是由大气中CO2的吸收引起的。
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 /ˈɔːrɡənaɪzər/

organizer

组织者
Meaning
a person who arranges or coordinates activities, events, or groups; a tool or item used to keep things in order
Example
She worked as the main organizer of the international conference.
她是这次国际会议的主要组织者。
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。
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。
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 noun /ˌɔːrnɪˈθɒlədʒɪst/

ornithologist

鸟类学家
Meaning
a scientist who studies birds
Example
The ornithologist spent years studying migratory birds.
这位鸟类学家花了多年时间研究迁徙鸟类。
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。
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。
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 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。
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。
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 noun /ˌɔːrəˈtɔːri.oʊ/

oratorio

宗教音乐作品
Meaning
A large-scale musical composition for orchestra, choir, and soloists, usually on a sacred theme, performed without costumes or scenery.
Example
Handel's 'Messiah' is one of the most famous oratorios ever written.
亨德尔的《弥赛亚》是最著名的宗教音乐作品之一。
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, 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.
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 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。
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。
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。
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。
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。
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。
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。
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。
C2 verb /ˈɑːbdʒərˌɡeɪt/

objurgate

严厉批评
Meaning
to scold or rebuke severely
Example
The teacher objurgated the student for being dishonest.
老师因为学生不诚实而严厉批评了他。
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。
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。
C2 noun /ˈɒlɪv bɑːb/

Olive barb

橄榄鲃
Meaning
A small freshwater fish with olive-colored body and barbels
Example
The olive barb is commonly found in South Asian rivers.
橄榄鲃常见于南亚的河流中。
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。
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 /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。
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。
A2 adjective /ɒd/

Odd

奇怪的; 不寻常的; 不同于正常或预期的
Meaning
strange; unusual; different from what is normal or expected
Example
That's an odd way to solve the problem.
那是解决问题的一种奇怪方式。