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Added 7 October 2026

certain

/ˈsɜː.tən/ adjective

In Latin: certus, fidus Wiktionary

adjective Definition from WordNet 3.1, Princeton University. Pronunciation from Wiktionary, via Kaikki.org. More about certain at Wordnik → Where our words come from →

Definite but not specified or identified.
set aside a certain sum each week
Having or feeling no doubt or uncertainty; confident and assured.
felt certain of success
Established beyond doubt or question; definitely known.
what is certain is that every effect must have a cause

Origin

From Middle English certeyn, certein, certain, borrowed from Old French certain, from a Vulgar Latin unattested form *certānus, extended form of Latin certus (“fixed, resolved, certain”), of the same origin as cretus, past participle of cernere (“to separate, perceive, decide”). Displaced native Middle English wis, iwis (“certain, sure”) (from Old English ġewiss (“certain, sure”)) and alternative Middle English spelling sertane (“some, certain”).

From Wiktionary, via Kaikki.org (CC BY-SA)

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