certain ones: Certain of the members declined the invitation.

Nearby words

  1. cerro de punta,
  2. cerro gordo,
  3. cerro tololo inter-american observatory,
  4. cert,
  5. cert.,
  6. certainly,
  7. certainty,
  8. certed,
  9. certes,
  10. certif.


    for certain, without a doubt; surely: I know for certain that I have seen that face before.

Origin of certain

1250–1300; Middle English < Old French < Vulgar Latin *certānus, equivalent to Latin cert(us) sure, settled (cer- base of cernere to decide, + -tus past participle suffix) + -ānus -an

1. convinced, satisfied. See sure. 4. indubitable, incontestable, irrefutable, incontrovertible, obvious, plain, clear. 5. determined.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for certain

British Dictionary definitions for certain



(postpositive) positive and confident about the truth of something; convincedI am certain that he wrote a book
(usually postpositive) definitely knownit is certain that they were on the bus
(usually postpositive) sure; bound; destinedhe was certain to fail
decided or settled upon; fixedthe date is already certain for the invasion
unfailing; reliablehis judgment is certain
moderate or minimumto a certain extent
make certain of to ensure (that one will get something); confirm


for certain definitely; without a doubthe will win for certain


  1. known but not specified or namedcertain people may doubt this
  2. (as pronoun; functioning as plural)certain of the members have not paid their subscriptions
named but not knownhe had written to a certain Mrs Smith

Word Origin for certain

C13: from Old French, from Latin certus sure, fixed, from cernere to discern, decide

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for certain



c.1300, "determined, fixed," from Old French certain "reliable, sure, assured" (12c.), from Vulgar Latin *certanus, from Latin certus "sure, fixed, settled, determined" (also source of Italian certo, Spanish cierto), originally a variant past participle of cernere "to distinguish, decide," literally "to sift, separate" (see crisis).

Of persons, "full of confidence in one's knowledge or judgment," from mid-14c. Euphemistic use (of a certain age, etc.) attested from mid-18c. Certainer, certainest were common to c.1750, but have fallen from proper use for some reason. Expression for certain "assuredly" is attested by early 14c.

Online Etymology Dictionary, © 2010 Douglas Harper

Idioms and Phrases with certain


see for certain.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.