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ascertain

[ as-er-teyn ]
/ ˌés ərˈteÉȘn /
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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

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What are other ways to say ascertain?

To ascertain something is to determine it or learn it with certainty or assurance. How is ascertain different from the learn, discover, and detect? Find out on Thesaurus.com.

How to use ascertain in a sentence

British Dictionary definitions for ascertain

ascertain
/ (ˌésəˈteÉȘn) /

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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