as·​cer·​tain | \ ˌa-sər-ˈtān How to pronounce ascertain (audio) \
ascertained; ascertaining; ascertains

Definition of ascertain

transitive verb

1 : to find out or learn with certainty ascertain the truth trying to ascertain the cause of the fire information that can be easily ascertained on the Internet
2 archaic : to make certain, exact, or precise

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Other Words from ascertain

ascertainable \ -​ˈtā-​nə-​bəl How to pronounce ascertainable (audio) \ adjective
ascertainment \ -​ˈtān-​mənt How to pronounce ascertainment (audio) \ noun

Choose the Right Synonym for ascertain

discover, ascertain, determine, unearth, learn mean to find out what one did not previously know. discover may apply to something requiring exploration or investigation or to a chance encounter. discovered the source of the river ascertain implies effort to find the facts or the truth proceeding from awareness of ignorance or uncertainty. attempts to ascertain the population of the region determine emphasizes the intent to establish the facts definitely or precisely. unable to determine the origin of the word unearth implies bringing to light something forgotten or hidden. unearth old records learn may imply acquiring knowledge with little effort or conscious intention (as by simply being told) or it may imply study and practice. I learned her name only today learning Greek

Examples of ascertain in a Sentence

We look at digital media—images, audio and video—and we try to ascertain whether or not they've been manipulated. We use mathematical and computational techniques to detect alterations in them. — Claudia Dreifus, New York Times, 2 Oct. 2007 Currently, an official trying to ascertain road damage in the aftermath of an earthquake might have to keep one eye on the TV news while listening to both radio traffic reports and the police scanner. Since most of these data are available in digital form, the software could take them all in, process them and present a report outlining the best evacuation routes. — Kevin Hogan, Technology Review, April 2002 With an equation linking the money wage to prices, the degree of inflation could be ascertained. — Sidney Weintraub, Modern Economic Thought, (1977) 1993
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Recent Examples on the Web

Collecting information from as many sources as possible is important to ascertaining the truth. Kelebogile Zvobgo, The Conversation, "Maryland has created a truth commission on lynchings – can it deliver?," 14 June 2019 An inside report has revealed that West Ham are currently making advances to try and ascertain which Manchester United players may be available for purchase this summer., "Inside Report Reveals That West Ham Are Looking to Bring in Manchester United Players This Summer," 10 June 2018 Kathy Doherty, Chicago Metropolitan Battered Women’s Network executive director, said the nonprofit plans to add questions within its intake process to ascertain possible brain injuries, such as asking about headaches and memory loss. Alison Bowen,, "Research on NFL players' brains might help survivors of domestic violence in Chicago," 19 Apr. 2018 Reuters recently reported, for example, that immigration authorities in Canada have been using DNA and ancestry websites to ascertain the nationality of migrants. John Brandon, Fox News, "Could hackers steal your DNA and sell it?," 21 Aug. 2018 Though only Americans 18 and older were surveyed, additional interviews were conducted with members of this age cohort to ascertain what was troubling young people. Isaac Stanley-becker, The Seattle Times, "69 percent of Americans are stressed about the country’s future, says new survey," 30 Oct. 2018 Boerhaave stressed the importance of ascertaining complete medical histories in conjunction with completing autopsies. Maude Campbell, Popular Mechanics, "The Complete History of the Autopsy," 26 Dec. 2018 The Trump administration is throwing up so many conflicting versions of reality that simply ascertaining what is and is not true requires rigorous effort. Lauren Duca, Teen Vogue, "Donald Trump Is Still Gaslighting America. I Really Care. Do u?," 23 June 2018 Four other attorneys on Mueller's team of 17 had no affiliation or their affiliation couldn't be ascertained, and Mueller himself is a Republican. Amber Phillips, Washington Post, "Breaking down Trump’s new conspiracy theory that Mueller’s team will meddle in the midterms," 29 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ascertain.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of ascertain

15th century, in the meaning defined at sense 2

History and Etymology for ascertain

Middle English acertainen to inform, give assurance to, from Anglo-French acerteiner, from a- (from Latin ad-) + certein, certain certain

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Statistics for ascertain

Last Updated

21 Jun 2019

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Time Traveler for ascertain

The first known use of ascertain was in the 15th century

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More Definitions for ascertain


as·​cer·​tain | \ ˌa-sər-ˈtān How to pronounce ascertain (audio) \
ascertained; ascertaining

Kids Definition of ascertain

: to find out with certainty Police tried to ascertain the cause of the accident.

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