free from doubt or reservation; confident; sure:
I am certain he will come.
destined; sure to happen (usually followed by an infinitive):
He is certain to be there.
inevitable; bound to come:
They realized then that war was certain.
established as true or sure; unquestionable; indisputable:
It is certain that he tried.
fixed; agreed upon; settled:
on a certain day; for a certain amount.
definite or particular, but not named or specified:
A certain person phoned. He had a certain charm.
that may be depended on; trustworthy; unfailing; reliable:
His aim was certain.
some though not much:
a certain reluctance.
Certain of the members declined the invitation.
for certain, without a doubt; surely:
I know for certain that I have seen that face before.
(postpositive) positive and confident about the truth of something; convinced: I am certain that he wrote a book
(usually postpositive) definitely known: it is certain that they were on the bus
(usually postpositive) sure; bound; destined: he was certain to fail
decided or settled upon; fixed: the date is already certain for the invasion
unfailing; reliable: his judgment is certain
moderate or minimum: to a certain extent
make certain of, to ensure (that one will get something); confirm
for certain, definitely; without a doubt: he will win for certain
known but not specified or named: certain people may doubt this
(as pronoun; functioning as plural): certain of the members have not paid their subscriptions
named but not known: he had written to a certain Mrs Smith
c.1300, “determined, fixed,” from Old French certain “reliable, sure, assured” (12c.), from Vulgar Latin *certanus, from Latin certus “sure, fixed, settled, determined” (also source of Italian certo, Spanish cierto), originally a variant past participle of cernere “to distinguish, decide,” literally “to sift, separate” (see crisis).
Of persons, “full of confidence in one’s knowledge or judgment,” from mid-14c. Euphemistic use (of a certain age, etc.) attested from mid-18c. Certainer, certainest were common to c.1750, but have fallen from proper use for some reason. Expression for certain “assuredly” is attested by early 14c.
see: for certain
with certainty; without doubt; assuredly: I’ll certainly be there. yes, of course: Certainly, take the keys. surely; to be sure: He certainly is successful. adverb with certainty; without doubt: he certainly rides very well sentence substitute by all means; definitely: used in answer to questions adv. c.1300, in all main modern senses, from certain + […]
the state of being certain. something certain; an assured fact. for / of a certainty, certainly; without a doubt: I suspect it, but I don’t know it for a certainty. noun (pl) -ties the condition of being certain something established as certain or inevitable for a certainty, without doubt n. c.1300, certeynte, “surety, pledge,” from […]
abbreviation (in Britain) Certificate in Education
certainly; in truth. adverb (archaic) with certainty; truly adv. mid-13c., from Old French certes, from Vulgar Latin certas, from Latin certe, adverb from certus (see certain).