from The American Heritage® Dictionary of the English Language, 5th Edition.

  • intransitive verb To confirm formally as true, accurate, or genuine.
  • intransitive verb To guarantee as meeting a standard.
  • intransitive verb To acknowledge in writing on the face of (a check) that the signature of the maker is genuine and that there are sufficient funds on deposit for its payment.
  • intransitive verb To issue a license or certificate to.
  • intransitive verb To declare to be in need of psychiatric treatment or confinement.
  • intransitive verb Archaic To inform positively; assure.
  • intransitive verb To vouch for the authenticity of something.

from The Century Dictionary.

  • To assure or make certain (of); give certain information to; tell positively: applied to persons, and followed by of before the thing told about, or by that before a verb and its nominative: as, I certified you of the fact.
  • To give certain information of; make clear, definite, or certain; vouch for: applied to things.
  • To testify to or vouch for in writing; make a declaration of in writing under hand, or hand and seal; make known or establish as a fact.
  • To testify; declare the truth; make a certification or certificate.

from the GNU version of the Collaborative International Dictionary of English.

  • transitive verb To give cetain information to; to assure; to make certain.
  • transitive verb To give certain information of; to make certain, as a fact; to verify.
  • transitive verb To testify to in writing; to make a declaration concerning, in writing, under hand, or hand and seal.
  • transitive verb A bank check, the validity of which is certified by the bank on which it is drawn.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • verb transitive to attest to as the truth or meeting a standard

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • verb guarantee as meeting a certain standard
  • verb provide evidence for; stand as proof of; show by one's behavior, attitude, or external attributes
  • verb declare legally insane
  • verb guarantee payment on; of checks
  • verb authorize officially


from The American Heritage® Dictionary of the English Language, 4th Edition

[Middle English certifien, from Old French certifier, from Late Latin certificāre : Latin certus, certain; see certain + Latin -ficāre, -fy.]


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