follow Dictionary.com

Get the details behind our redesign

ascertain

[as-er-teyn] /ˌæs ərˈteɪn/
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.
Origin
1400-1450
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 forms
ascertainable, adjective
ascertainably, adverb
ascertainer, noun
ascertainment, noun
nonascertainable, adjective
nonascertainableness, noun
nonascertainably, adverb
nonascertainment, noun
preascertain, verb (used with object)
preascertainment, noun
unascertainable, adjective
unascertainably, adverb
unascertained, adjective
well-ascertained, adjective
Synonym Study
1. See learn.
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source
British Dictionary definitions for un ascertained

ascertain

/ˌæsəˈteɪn/
verb (transitive)
1.
to determine or discover definitely
2.
(archaic) to make certain
Derived Forms
ascertainable, adjective
ascertainably, adverb
ascertainment, noun
Word Origin
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
Cite This Source
Word Origin and History for un ascertained
ascertain
early 15c., "to inform, to give assurance," from O.Fr. acertener "to assure" (13c.), from a "to" + certain "certain" (see certain). Modern meaning of "to find out for sure by experiment or investigation" is first attested 1794.
Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source

Word of The Day

Difficulty index for ascertain

Some English speakers likely know this word

Word Value for un

2
4
Scrabble Words With Friends