1. Sure, positive, not doubting.
    I was certain of my decision.
  2. Determined; resolved.
  3. Not to be doubted or denied; established as a fact.
  4. Actually existing; sure to happen; inevitable.
    Bankruptcy is the certain outcome of your constant gambling and lending.
  5. Unfailing; infallible.
  6. Fixed or stated; regular; determinate.
  7. Not specifically named; indeterminate; indefinite; one or some; sometimes used independently as a noun, and meaning certain persons.

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