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. adjective
    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
    known for certain
    indisputable, sure
    impossible to doubt or dispute
    sure as shooting
    absolutely certain
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    not established beyond doubt; still undecided or unknown
    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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  2. adjective
    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”
    precise; explicit and clearly defined
  3. adjective
    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
    capable of being foretold
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    not certain to occur; not inevitable
    chancy, flukey, fluky, iffy
    subject to accident or chance or change
    uncertain because of uncontrollable circumstances
    up in the air
    not yet determined
    not capable of being foretold
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  4. adjective
    established irrevocably
    synonyms: sealed
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    uncertain, unsealed
    not established or confirmed
  5. adjective
    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
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    incertain, uncertain, unsure
    lacking or indicating lack of confidence or assurance
    uncertain or unable to decide about what course to follow
    doubtful, dubious
    fraught with uncertainty or doubt
    acting with uncertainty or hesitance or lack of confidence
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  6. adjective
    exercising or taking care great enough to bring assurance
    “be certain to disconnect the iron when you are through”
    synonyms: sure
    exercising caution or showing care or attention
  7. adjective
    reliable in operation or effect
    “a quick and certain remedy”
    synonyms: sure
    dependable, reliable
    worthy of reliance or trust
Word Family
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