O

(58 words)

obese

adjective

extremely fat in a way that is dangerous for health:

obesity

noun [ U ]

the fact of being extremely fat, in a way that is dangerous for health:

object

noun

[ C usually singular ] a reason for doing something, or the result you wish to achieve by doing it:

objectively

adverb

in a way that is based on facts and not influenced by personal beliefs or feelings:

obligatory

adjective

If something is obligatory, you must do it because of a rule or law, etc.:

oblige

verb

[ I or T ] to please or help someone, especially by doing something they have asked you to do:

observation

noun

[ C ] formal a remark about something that you have noticed:

observe

verb [ T ]

formal to notice or see:

obsolete

adjective

not in use any more, having been replaced by something newer and better or more fashionable:

obstacle

noun [ C ]

something that blocks you so that movement, going forward, or action is prevented or made more difficult:

occasional

adjective

not happening or done often or regularly:

occupation

noun

[ C ] a regular activity or hobby:

occupy

verb [ T ]

(of an army or group of people) to move into and take control and/or possession of a place:

occurrence

HAPPENING

noun

[ C ] something that happens:

EXISTING

[ U ] the fact of something existing, or how much of it exists:

odds

noun [ plural ]

the probability (= how likely it is) that a particular thing will or will not happen:

of

preposition

about; relating to:

off the record

If someone says something off the record, they do not want it to be publicly reported:

office

noun

[ C or U ] a position of authority and responsibility in a government or other organization:

officially

adverb

formally and in a way agreed to or arranged by people in positions of authority:

the old days

times in the past:

omit

verb [ T ]

to fail to include or do something:

all at once

suddenly and unexpectedly:

one

formal any person, but not a particular person:

oneself

pronoun formal

the reflexive form of the pronoun ‘one’ when it refers to people in general or to the person speaking:

open

adjective

[ after verb ] available; not limited:

opening

adjective [ before noun ]

happening at the beginning of an event or activity:

openly

adverb

without hiding any of your thoughts or feelings:

open-minded

adjective

willing to consider ideas and opinions that are new or different to your own:

operation

noun

[ U ] the fact of operating or being active:

[ C ] a business organization:

[ C ] an activity that is planned to achieve something:

be opposed to sth

to disagree with a principle or plan:

opposition

noun

[ U ] strong disagreement:

the opposition

[ S, + sing/pl verb ]

the team or person being played against in a sports competition:

opt

verb [ I ]

to make a choice, especially of one thing or possibility instead of others:

optimist

noun [ C ]

someone who always believes that good things will happen:

have no option (but to do something)

to have to do a particular thing because there is no possibility of doing anything else:

organ

noun

[ C ] a part of the body of an animal or plant that performs a particular job:

organization

noun

[ U ] the way in which something is done or arranged

origin

noun

[ U ] where a person was born:

other than

different from or except:

or other

informal

used when you cannot or do not want to be exact about the information you are giving:

out

adverb, preposition

informal not accurate:

outcome

noun [ C usually singular ]

a result or effect of an action, situation, etc.:

outlook

noun

[ S ] the likely future situation:

outnumber

verb [ T ]

to be greater in number than someone or something:

outside

adjective, adverb, preposition

[ before noun ] coming from another place or organization:

outweigh

verb [ T ]

to be greater or more important than something else:

overcrowded

adjective

containing too many people or things:

overdo

verb [ T ]

to do something in a way that is too extreme:

overdraft

noun [ C ]

an amount of money that a customer with a bank account is temporarily allowed to owe to the bank, or the agreement that allows this:

overdrawn

adjective

having taken more money out of your bank account than the account contained, or (of a bank account) having had more money taken from it than was originally in it:

overestimate

verb [ I or T ]

to think that something is or will be greater, more extreme, or more important than it really is:

overtake

verb

[ T ] to go past something by being a greater amount or degree:

overview

noun [ C ]

a short description of something that provides general information about it, but no details:

overwhelm

verb

[ T usually passive ] to cause someone to feel sudden strong emotion:

overwhelming

adjective

difficult to fight against:

very great or very large:

overworked

adjective

having to work too much:

ownership

noun [ U ]

the fact that you own something:

ozone

noun [ U ]

a poisonous form of oxygen