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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。
B2 adjective /ˌɑːp.təˈmɪs.tɪk/

optimistic

乐观的
Meaning
hopeful and confident about the future
Example
She is optimistic about the success of her new project.
她对新项目的成功持乐观态度。
C1 noun /ˌɑːsɪˈleɪʃən/

oscillation

摆动
Meaning
The movement back and forth at a regular speed.
Example
The oscillation of the pendulum controls the clock.
摆锤的摆动控制着时钟。
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 /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 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。
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。
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 /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。
B2 noun /ˈoʊtˌmiːl/

oatmeal

燕麦粥
Meaning
A type of porridge made from ground oats, often eaten for breakfast.
Example
She eats a bowl of oatmeal every morning for breakfast.
她每天早晨吃一碗燕麦粥当早餐。
C1 adjective /oʊˈbiːs/

obese

肥胖
Meaning
Extremely overweight; having an excessive amount of body fat.
Example
The doctor advised the obese patient to adopt a healthier lifestyle.
医生建议肥胖的病人采取更健康的生活方式。
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。
C1 noun /ˈoʊvərˌtoʊn/

overtone

微妙的含义
Meaning
A subtle quality, implication, or additional meaning beyond the obvious.
Example
His speech had political overtones that were hard to ignore.
他的演讲具有政治性含义，难以忽视。
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 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 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 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。
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 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。
A1 adjective /ˈʌðər/

other

其他
Meaning
used to refer to something different from the one already mentioned or known
Example
I don't want this one, I will take the other one.
我不想要这个，我会拿另一个。
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。
C2 noun /ˈoʊdiəm/

odium

憎恶
Meaning
general or widespread hatred or disgust directed toward someone as a result of their actions
Example
The scandal brought public odium on the corrupt minister.
丑闻让腐败的部长蒙受了公众的憎恶。
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。
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。
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 adjective /ɒˈstɛnsəbl/

ostensible

表面上
Meaning
stated or appearing to be true, but not necessarily so
Example
His ostensible reason for leaving was illness, but many doubted it.
他离开的表面上原因是生病，但许多人对此表示怀疑。
B1 noun /ˈɔːfɪsər/

officer

警官
Meaning
a person in a position of authority, especially in law enforcement
Example
The officer gave him a ticket for speeding.
警官因超速给了他一张罚单。
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 /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 interjection /oʊ/

oh

哦
Meaning
used to express surprise, realization, or understanding
Example
Oh, I didn't know you were here!
哦，我不知道你在这里！
C2 noun /ˌɒpəˈrɛtə/

operetta

轻歌剧
Meaning
a short opera with light and humorous themes
Example
The theater staged a famous operetta by Gilbert and Sullivan.
剧院上演了吉尔伯特与沙利文的著名轻歌剧。
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 /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。
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 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。
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。
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。
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。
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。
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。
A1 verb /ˈoʊpən/

open

打开
Meaning
to move something so as to allow access; to begin
Example
Please open the door for me.
请为我打开门。
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 /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 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 /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 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。
A1 pronoun /aʊərz/

ours

我们的
Meaning
belonging to or associated with us
Example
This victory is ours.
这个胜利是我们的。
C1 adverb /ˈaʊtwədli/

Outwardly

表面上; 外观上;
Meaning
on the surface; externally; in appearance
Example
Outwardly, he seemed calm, but inside he was nervous.
表面上，他看起来很冷静，但内心却很紧张。
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 /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 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 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 verb /ˌoʊvərˈduː/

overdo

做得过火
Meaning
to do something too much; to exaggerate or carry to excess
Example
Don't overdo the exercise on your first day at the gym.
第一天去健身房时不要运动过度。
C1 noun ˌoʊ.vɚˈɡreɪ.zɪŋ

overgrazing

过度放牧
Meaning
The practice of allowing livestock to graze to the point of damaging vegetation.
Example
Overgrazing leads to soil erosion and loss of biodiversity.
过度放牧导致土壤侵蚀和生物多样性的丧失。
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 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。
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。
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。
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。
B2 verb /əˈrɪdʒɪneɪt/

originate

起源
Meaning
to come into existence; to begin; to create or produce
Example
The tradition originated in ancient times.
这个传统起源于古代。
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。
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。
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。
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 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。
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。
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。
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 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。
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。
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。
B1 adjective /ˌoʊvərˈweɪt/

overweight

超重
Meaning
heavier than is considered healthy or normal
Example
The doctor advised him to lose weight as he was overweight.
医生建议他减肥，因为他超重。
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 /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 adjective /ˌoʊvərˈbloʊn/

overblown

夸张
Meaning
excessively exaggerated or inflated
Example
The controversy was overblown by the media.
媒体过度夸大了争议。
B1 verb /əbˈzɜːrv/

observe

观察
Meaning
to watch carefully; to notice or perceive something
Example
Scientists observe the behavior of animals in the wild.
科学家观察野生动物的行为。
B1 verb /ˈɒpəreɪt/

operate

操作
Meaning
to function; to control or manage; to perform surgery
Example
The surgeon will operate on the patient tomorrow.
外科医生明天将为病人做手术。
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。
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。
B2 adjective /əˈfen.sɪv/

Offensive

冒犯的; 侮辱的; 攻击性的
Meaning
causing displeasure or resentment; insulting; aggressive
Example
His offensive remarks hurt everyone's feelings.
他的冒犯言论伤害了每个人的感情。
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。
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 /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 /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。
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。
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。
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。
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。
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 /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 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 /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。
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。
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。
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 /ˈɔːrθədɑːks/

orthodox

Meaning
conforming to traditional beliefs or practices
Example
He comes from a very orthodox family.
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。
C2 verb /ˌaʊtməˈnuːvər/

outmaneuver

巧妙地战胜
Meaning
to gain an advantage over an opponent by skillful or clever action
Example
The smaller company managed to outmaneuver its larger rival.
小公司成功地战胜了它的大对手。
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 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。
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.
C1 noun /ˈoʊ.mən/

Omen

未来好运或厄运的征兆
Meaning
an event regarded as a sign of future good or bad luck
Example
Many people consider a black cat crossing your path a bad omen.
许多人认为一只黑猫横穿你的路是一个坏预兆。
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。
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。
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。
C1 adjective /ɒmˈnɪv.ər.əs/

Omnivorous

杂食性动物
Meaning
eating both plants and animals; feeding on various kinds of food
Example
Bears are omnivorous animals that eat both plants and meat.
熊是杂食性动物，吃植物和肉。
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。
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 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。
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。
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。
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。
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。
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 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。
A1 adjective /oʊld/

old

旧的
Meaning
having lived for a long time; not new or young
Example
He still drives his old car.
他仍然开着他的旧车。
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。
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。
B2 noun /ˌɑb.zɚˈveɪ.ʃən/

Observation

观察
Meaning
the action of watching something carefully; a comment or remark
Example
The scientist made careful observations of the experiment.
科学家仔细观察了实验。
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。
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。