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ascertain

[ as-er-teyn ]
/ ˌæs ərˈteɪn /
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See synonyms for: ascertain / ascertained / ascertaining / ascertainable on Thesaurus.com
verb (used with object)
to find out definitely; learn with certainty or assurance; determine: to ascertain the facts.
Archaic. to make certain, clear, or definitely known.
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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 + certaincertain

OTHER WORDS FROM ascertain

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Words related to ascertain

confirm, determine, divine, double-check, find out, verify, check, dig, discover, establish, eye, eyeball, fix, identify, learn, peg, read, see, settle, size

How to use ascertain in a sentence

British Dictionary definitions for ascertain

ascertain
/ (ˌæsəˈteɪn) /
verb (tr)
to determine or discover definitely
archaic to make certain

Derived forms of ascertain

ascertainable, 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
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