If you describe someone as opportunist, you are critical of them because they take advantage of any situation in order to gain money or power, without considering whether their actions are right or wrong.
[disapproval]
...corrupt and opportunist politicians.
An opportunist is someone who is opportunist.
Like most successful politicians, Sinclair was an opportunist.
Car thieves are opportunists.
2. adjective [usually ADJECTIVE noun]
Opportunist actions are not planned, but are carried out in order to take advantage of a situation that has just occurred.
He made the game safe with a brilliant opportunist goal.
opportunist in British English
(ˌɒpəˈtjuːnɪst)
noun
1.
a person who adapts his or her actions, responses, etc, to take advantage of opportunities, circumstances, etc
adjective
2.
taking advantage of opportunities and circumstances in this way
Derived forms
opportunism (ˌopporˈtunism)
noun
Examples of 'opportunist' in a sentence
opportunist
Put himself about and yet another opportunist goal.
The Sun (2013)
It is not yet known whether it was a targeted theft or the work of an opportunist thief.
Times, Sunday Times (2009)
He came up with a couple of typical opportunist goals to put his team firmly in control of the practice game.
The Sun (2006)
But he has been more silly than corrupt, opportunist not dishonest.
Times, Sunday Times (2008)
All his goals were opportunist.
The Sun (2014)
That changed while she was sunbathing in a public park and an opportunist thief made off with a friend's mobile phone.
Times, Sunday Times (2016)
THE political opportunist of the week?
The Sun (2014)
In other languages
opportunist
British English: opportunist ADJECTIVE
An opportunist takes advantage of any situation in order to gain money or power.
...corrupt and opportunist politicians.
American English: opportunist
Brazilian Portuguese: oportunista
Chinese: 机会主义的
European Spanish: oportunista
French: opportuniste
German: opportunistisch
Italian: opportunista
Japanese: 日和見主義の
Korean: 기회주의자인
European Portuguese: oportunista
Latin American Spanish: oportunista
British English: opportunist NOUN
An opportunist is someone who is opportunist.
Like most successful politicians, he was an opportunist.