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1 ADJ [ADJ n] You use certain to indicate that you are referring to one particular thing, person, or group, although you are not saying exactly which it is. □  There will be certain people who'll say 'I told you so!'. □  Leaflets have been air dropped telling people to leave certain areas.

2 QUANT When you refer to certain of a group of people or things, you are referring to some particular members of that group. [FORMAL ] □ [+ of ] They'll have to give up completely on certain of their studies.

3 ADJ You can use a certain before the name of a person in order to indicate that you do not know the person or anything else about them. □  She managed to arrange for them to be hidden in the house of a certain Father Boduen.

4 ADJ You use a certain to indicate that something such as a quality or condition exists, and often to suggest that it is not great in amount or degree. □  That was the very reason why he felt a certain bitterness. SYNONYMS certain ADJ ➊1

sure:She was no longer sure how she felt about him.

positive:'She's never late. You sure she said eight?'—'Positive.'

confident:I am confident that everything will come out right in time.

satisfied:People must be satisfied that the treatment is safe.

convinced:He was convinced that I was part of the problem.

cer|tain|ly ◆◆◇ /sɜː ^r t ^ə nli/

1 ADV You use certainly to emphasize what you are saying when you are making a statement. [EMPHASIS ] □  The bombs are almost certainly part of a much bigger conspiracy. □  Today's inflation figure is certainly too high. □  Certainly, pets can help children develop friendship skills.

2 ADV You use certainly when you are agreeing with what someone has said. □  'In any case you remained friends.'—'Certainly.' □  'You keep out of their way don't you?'—'I certainly do.'

3 ADV You say certainly not when you want to say 'no' in a strong way. [EMPHASIS ] □  'Perhaps it would be better if I withdrew altogether.'—'Certainly not!' SYNONYMS certainly ADV 1

definitely:Something should definitely be done about that.

without (a) doubt:The refugees, without a doubt, are the most vulnerable.

undoubtedly:Hanley is undoubtedly a great player.

unquestionably:He is unquestionably a star.

cer|tain|ty /sɜː ^r t ^ə nti/ (certainties )

1 N‑UNCOUNT [oft with N , N that] Certainty is the state of being definite or of having no doubts at all about something. □  I have told them with absolute certainty there'll be no change of policy. □ [+ about ] If you buy from reputable dealers you have more certainty about what you're getting.

2 N‑UNCOUNT [oft a N ] Certainty is the fact that something is certain to happen. □  A general election became a certainty three weeks ago. □ [+ of ] …the certainty of more violence and bloodshed.

3 N‑COUNT [usu pl] Certainties are things that nobody has any doubts about. □  There are no certainties in modern Europe.

cer|ti|fi|able /sɜː ^r t I fa I əb ^ə l/ ADJ If you describe someone as certifiable , you think that their behaviour is extremely unreasonable or foolish. [mainly BRIT , INFORMAL , DISAPPROVAL ] □  …if he can convince the committee that he is not certifiable.

cer|tifi|cate /sə ^r t I f I kət/ (certificates )