Dictionary.com
definitions
  • synonyms

ascertain

[as-er-teyn]
verb (used with object)
  1. to find out definitely; learn with certainty or assurance; determine: to ascertain the facts.
  2. Archaic. to make certain, clear, or definitely known.
Show More

Origin of ascertain

1400–50; late Middle English, variant of assertain, acertain < Middle French acertain- (tonic stem of acertener to make certain), equivalent to a- a-5 + certain certain
Related formsas·cer·tain·a·ble, adjectiveas·cer·tain·a·bly, adverbas·cer·tain·er, nounas·cer·tain·ment, nounnon·as·cer·tain·a·ble, adjectivenon·as·cer·tain·a·ble·ness, nounnon·as·cer·tain·a·bly, adverbnon·as·cer·tain·ment, nounpre·as·cer·tain, verb (used with object)pre·as·cer·tain·ment, nounun·as·cer·tain·a·ble, adjectiveun·as·cer·tain·a·bly, adverbun·as·cer·tained, adjectivewell-as·cer·tained, adjective

Synonym study

1. See learn.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for unascertainable

Historical Examples of unascertainable

  • There was first the Procession of the Maestranza, of unascertainable antiquity.

    Diversions in Sicily

    H. Festing Jones

  • Antonyms: unknowable, unascertainable, incognoscible, unrecognizable.

    Putnam's Word Book

    Louis A. Flemming

  • The composition of the earliest inks has not yet been obtained and, likely, is unascertainable.

    The Reign of the Manuscript

    Perry Wayland Sinks

  • During the seventh century many sanguinary battles were fought, the sites of which are now unascertainable.

  • The exact date of his advent to that place seems to be unascertainable, but it was more than fifty years ago.

    The Old Pike

    Thomas B. Searight


British Dictionary definitions for unascertainable

ascertain

verb (tr)
  1. to determine or discover definitely
  2. archaic to make certain
Show More
Derived Formsascertainable, adjectiveascertainably, adverbascertainment, noun

Word Origin for ascertain

C15: from Old French acertener to make certain
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 unascertainable

ascertain

v.

early 15c., "to inform, to give assurance," from Anglo-French acerteiner, Old French acertener "to assure, certify" (13c.), from a "to" (see ad-) + certain "certain" (see certain). Modern meaning of "find out for sure by experiment or investigation" is first attested 1794. Related: Ascertained; ascertaining.

Show More
Online Etymology Dictionary, © 2010 Douglas Harper