1

certain

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adjective cer·tain \ ˈsər-tᵊn \

Definition of certain

1 :fixed, settled
  • a certain percentage of the profit
2 :of a specific but unspecified character, quantity, or degree
  • the house has a certain charm
3 a :dependable, reliable
  • a certain remedy for the disease
b :known or proved to be true :indisputable
  • it is certain that we exist
4 a :inevitable
  • the certain advance of age
b :incapable of failing :destined used with a following infinitive
  • she is certain to do well
5 :assured in mind or action
  • I am certain they are right
for certain
:as a certainty :assuredly
  • the cause is not known for certain
of a certain age
:of a somewhat advanced age :no longer young
  • remembered by people of a certain age

Examples of certain in a Sentence

  1. I'm fairly certain that I'll be on time.

  2. a certain person told me that today is your birthday

Recent Examples of certain from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'certain.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of certain

Middle English certeyn, certayne, borrowed from Anglo-French certein, certain, going back to Vulgar Latin *certānus, from Latin certus "fixed, settled, indisputable," originally past participle of cernere "to sift, discern, decide, determine" (going back to an Indo-European present stem *kri-n-, verbal adjective *kri-to-, from a verbal base *krei̯̯(h1)- "sift, separate," whence Greek krī́nein "to separate, choose, decide," verbal adjective kritós, Welsh gogrynu "to sift") + -ānus + 2-an

certain Synonyms

Synonym Discussion of certain

sure, certain, positive, cocksure mean having no doubt or uncertainty. sure usually stresses the subjective or intuitive feeling of assurance.
    • felt sure that I had forgotten something
certain may apply to a basing of a conclusion or conviction on definite grounds or indubitable evidence.
    • police are certain about the cause of the fire
positive intensifies sureness or certainty and may imply opinionated conviction or forceful expression of it.
    • I'm positive that's the person I saw
cocksure implies presumptuous or careless positiveness.
    • you're always so cocksure about everything

2

certain

pronoun, plural in construction

Definition of certain

:certain ones
  • certain of my generation
  • —W. B. Yeats

Origin and Etymology of certain

Middle English certyn, derivative of certeyn 1certain — see 1certain



CERTAIN Defined for English Language Learners

certain

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adjective

Definition of certain for English Language Learners

  • : not having any doubt about something : convinced or sure

  • —used with it to say that something is known to be true or correct

  • —used to refer to something or someone that is not named specifically


CERTAIN Defined for Kids

1

certain

play
adjective cer·tain \ ˈsər-tᵊn \

Definition of certain for Students

1 :without any doubt :sure
  • Are you certain you saw her?
2 :known to be true
  • It's certain that they were here.
3 :known but not named
  • A certain person told me.
4 :being fixed or settled
  • a certain percentage of the profit
5 :bound by the way things are
  • Our plan is certain to succeed.
6 :sure to have an effect
  • a certain cure

2

certain

pronoun

Definition of certain for Students

:known ones that are not named
  • Certain of the students could work harder.


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