Certain

Part of speech: adjective

Pronunciation: /ˈsɜː.tən/

Definitions

1. Confident about something being true or sure to happen
2. Having no doubt regarding the truth or outcome of an event ; known or decided without any ambiguity
3. Showing assurance in belief or decision ; firmly fixed or clearly identified

Etymology: The most striking thing about "certain" is how it displaced a native English word. Before "certain" took over, English speakers said "wis" or "iwis" for "sure," a word descended from Old English "ġewiss," which survives today only in the archaic "iwis" and in "unwitting." Middle English borrowed the French "certain" instead, and it pushed the older word out of everyday use. The French word came from a Vulgar Latin form, "certānus," which was an extended version of the Latin "certus," meaning "fixed" or "resolved." That Latin adjective shares its origin with "cretus," the past participle of "cernere," a verb meaning "to separate," "perceive," or "decide." The sense of mental settledness, of having sifted things apart until one was sure, runs underneath the modern meaning.

Synonyms: sure, confident, assured, definite, unquestionable

Antonyms: uncertain, doubtful, ambiguous, indefinite, questionable