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 ascertainable (audio) \ adjective
ascertainment \ ˌa-​sər-​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 Laura Dudnick, a spokeswoman for the school district, said district staff has been meeting regularly to discuss the new school year for months and has been actively engaging families through town halls and surveys to ascertain their wishes. Heather Knight,, "SF school district already flunked distance learning. Why haven’t officials spent the summer cramming to ace it?," 11 July 2020 Due to the state of the remains, police have not been able to ascertain the age, gender, or ethnicity of the deceased individual. Eileen Mcmenamin, CNN, "Florida jogger finds decomposing human head on side of the road," 7 July 2020 Nyhan also said the company needs to ascertain whether the reversal created a loophole in its fact-checking initiative. Scott Waldman, Scientific American, "Climate Denial Spreads on Facebook as Scientists Face Restrictions," 6 July 2020 Who can go where under what conditions during the pandemic can be difficult to ascertain. Washington Post, "As Europeans embark on summer holidays, Americans have fewer options," 1 July 2020 But what specifically constitutes a crime under this law is much more difficult to ascertain. Haley Victory Smith, Washington Examiner, "Here's what we know so far about China's new 'national security' law for Hong Kong," 30 June 2020 Decisions are further complicated by the fact that with few exceptions, most prospective buyers cannot ascertain whether or not a home was previously flooded. USA Today, "Millions of Americans think they’re safe from flood waters. They aren’t.," 29 June 2020 In mid-May, the American Medical Association suggested that antibody tests should not be used to ascertain immunity or suggest an end to social distancing practices. Raisa Bruner, Time, "From Massages to Nasal Swabs: Inside XpresSpa's Tough Road to Becoming an Airport COVID-19 Testing Center," 23 June 2020 Additional testing by the National Veterinary Services Laboratories of the United States Department of Agriculture (USDA) confirmed the lab’s result—the standard procedure to officially ascertain a positive case of COVID-19 in an animal. Natasha Daly, National Geographic, "A German shepherd is first dog in the U.S. to test positive for the coronavirus," 4 June 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

14 Jul 2020

Cite this Entry

“Ascertain.” Dictionary, Merriam-Webster, Accessed 16 Jul. 2020.

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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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