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 \ ˌa-​sər-​ˈtā-​nə-​bəl How to pronounce ascertain (audio) \ adjective
ascertainment \ ˌa-​sər-​ˈtān-​mənt How to pronounce ascertain (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 President Trump has refused to concede to Mr. Biden, and some aspects of the transition were initially delayed when the General Services Administration waited to formally ascertain Mr. Biden’s victory. Sabrina Siddiqui, WSJ, "Biden Transition’s Pentagon Briefings Resume Amid Dispute," 30 Dec. 2020 The General Services Administration has yet to ascertain the election, which triggers the formal transition and gives the Biden team funding and access to federal agencies. TheWeek, "Some Trump officials are stealthily reaching out to Biden's transition team," 19 Nov. 2020 Congress will call a joint session on Jan. 6 to ascertain the Electoral College results after the new Congress takes its seats on Jan. 3. Washington Examiner, "OANN won't recognize Biden as president-elect until Congress certifies Electoral College," 16 Dec. 2020 The agency has said that Murphy cannot yet ascertain the winner of the presidential race, citing the precedent established after the 2000 election, when court battles over the Florida recount delayed the transition by several weeks. Grace Segers, CBS News, "What is the GSA, and what role does it play in the presidential transition?," 11 Nov. 2020 Under the 57-year-old Presidential Transition Act, the administrator of the General Services Administration -- currently a Trump appointee -- is empowered to formally ascertain the apparent winner. Jennifer A Dlouhy,, "Trump-to-Biden Handoff Stalls as President Rejects Outcome," 8 Nov. 2020 The breach presents a major challenge to the incoming administration of President-elect Joe Biden as officials investigate what information was stolen and try to ascertain what it will be used for. Christopher Bing, The Christian Science Monitor, "Hackers breach US Treasury and Commerce Department. Russians?," 13 Dec. 2020 The team will also conduct contact tracing to ascertain Conner's contacts. Scott Gleeson, USA TODAY, "NFL coronavirus updates: Saints' Terron Armstead tests positive, to miss Week 12," 28 Nov. 2020 Just as a doctor might test someone’s blood to ascertain their risk of heart disease, Marigómez tracks signs of toxicity and stress in these biomarkers, which paint a portrait of the health of the mussel—and therefore its environment. Cathleen O’grady, Smithsonian Magazine, "The Race to Study Arctic Waters," 4 Nov. 2020

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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Time Traveler for ascertain

Time Traveler

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

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Statistics for ascertain

Last Updated

16 Jan 2021

Cite this Entry

“Ascertain.” Dictionary, Merriam-Webster, Accessed 1 Mar. 2021.

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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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