certain

When you're certain, you're sure about something. When you raise your hand to give the answer, you feel certain that you are correct.

Certain can mean "definite" or "sure to happen," like getting wet, a certain outcome of not having an umbrella in a rainstorm. It can also refer to a particular person or thing. You can use it avoid explaining something unnecessarily — you might say, "There are certain things I want to do when I get home." To avoid saying someone's name, you can say, "a certain person," as in, "A certain person left the kitchen a mess."

Definitions of certain
1

adj established beyond doubt or question; definitely known

“what is certain is that every effect must have a cause”
“it is certain that they were on the bus”
“his fate is certain
“the date for the invasion is certain
Synonyms:
definite
known for certain
indisputable, sure
impossible to doubt or dispute
sure as shooting
absolutely certain
Antonyms:
uncertain
not established beyond doubt; still undecided or unknown
indefinite
not decided or not known
up in the air
very uncertain
indeterminate, undetermined
not precisely determined or established; not fixed or known in advance
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adj definite but not specified or identified

“set aside a certain sum each week”
“to a certain degree”
certain breeds do not make good pets”
certain members have not paid their dues”
“a certain popular teacher”
“a certain Mrs. Jones”
Synonyms:
definite
precise; explicit and clearly defined

adj certain to occur; destined or inevitable

“he was certain to fail”
“his fate is certain
“"In this life nothing is certain but death and taxes"- Benjamin Franklin”
“he faced certain death”
Synonyms:
sure
bound, destined
(usually followed by `to') governed by fate
doomed, fated
(usually followed by `to') determined by tragic fate
foreordained, predestinate, predestined
established or prearranged unalterably
in for
certain to get or have
predictable
capable of being foretold
Antonyms:
uncertain
not certain to occur; not inevitable
chancy, flukey, fluky, iffy
subject to accident or chance or change
contingent
uncertain because of uncontrollable circumstances
up in the air
not yet determined
unpredictable
not capable of being foretold
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adj established irrevocably

Synonyms:
sealed
Antonyms:
uncertain, unsealed
not established or confirmed

adj having or feeling no doubt or uncertainty; confident and assured

“felt certain of success”
“was sure (or certain) she had seen it”
Synonyms:
sure
confident, convinced, positive
persuaded of; very sure
Antonyms:
incertain, uncertain, unsure
lacking or indicating lack of confidence or assurance
ambivalent
uncertain or unable to decide about what course to follow
doubtful, dubious
fraught with uncertainty or doubt
groping
acting with uncertainty or hesitance or lack of confidence
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adj exercising or taking care great enough to bring assurance

“be certain to disconnect the iron when you are through”
Synonyms:
sure
careful
exercising caution or showing care or attention

adj reliable in operation or effect

“a quick and certain remedy”
Synonyms:
sure
dependable, reliable
worthy of reliance or trust

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