to find out definitely; learn with certainty or assurance; determine: to ascertain the facts.
Archaic. to make certain, clear, or definitely known.
- as·cer·tain·a·ble, adjective
- as·cer·tain·a·bly, adverb
- as·cer·tain·er, noun
- as·cer·tain·ment, noun
- non·as·cer·tain·a·ble, adjective
- non·as·cer·tain·a·ble·ness, noun
- non·as·cer·tain·a·bly, adverb
- non·as·cer·tain·ment, noun
- pre·as·cer·tain, verb (used with object)
- pre·as·cer·tain·ment, noun
- un·as·cer·tain·a·ble, adjective
- un·as·cer·tain·a·bly, adverb
- un·as·cer·tained, adjective
- well-as·cer·tained, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use ascertain in a sentence
A word may survive and take a new meaning after its original meaning is no longer ascertainable.Assimilative Memory | Marcus Dwight Larrowe (AKA Prof. A. Loisette)
The influences of smoking and snuffing on politics and war are ascertainable.Tobacco; Its History, Varieties, Culture, Manufacture and Commerce | E. R. Billings.
Idiopathic diseases are those that have come of themselves, that is, without ascertainable cause.Essays In Pastoral Medicine | Austin Malley
It would serve no purpose except that of satisfying idle curiosity to draw up a list of all the master's ascertainable pupils.Frederick Chopin as a Man and Musician | Frederick Niecks
In the latter case, the time is uncertain; but the fact is ascertainable by the recipients becoming spiritually minded.
British Dictionary definitions for ascertain
to determine or discover definitely
archaic to make certain
- ascertainable, adjective
- ascertainably, adverb
- ascertainment, noun
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