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 Since not all those who have been out sick could get tested, the precise number of those who had confirmed COVID-19 is not possible to ascertain. NBC News, "Coronavirus patient receives standing ovation from hospital after 15-day battle," 7 Apr. 2020 His mission was to ascertain the advantage of establishing a commercial whaling base below the Antarctic Circle. Lucy Jakub, Harper's magazine, "A View to a Krill," 2 Mar. 2020 Clearly, the goal of this documentary isn’t to solve the mystery of her death or to ascertain whether there was foul play. Los Angeles Times, "Review: Natalie Wood’s death is still big business. In HBO’s new doc, her family fights back," 5 May 2020 The site asks users about their location, recent travel history and symptoms to ascertain whether or not someone needs to get tested. Aisha Salaudeen, CNN, "A new website is helping Nigerians check if they have coronavirus," 16 Apr. 2020 Travel continues to be strictly controlled, as people across the country must download apps ascertaining their health status before being allowed to check into hotels or board public transport. Jane Li, Quartz, "Wuhan’s traumatized residents warn that the lifting of lockdowns is “not the end”," 7 Apr. 2020 Reform Alliance will continue its work in ascertaining the highly coveted masks and distributing to the prisons that need it most. Rosy Cordero,, "JAY-Z and Meek Mill Donate over 100,000 Masks to Prisons to Prevent Coronavirus Spread," 6 Apr. 2020 Other types of behavior were subject to a more detailed and laborious case-by-case analysis to ascertain whether the conduct in question unreasonably restrained trade. Amitrajeet A. Batabyal, The Conversation, "How the T-Mobile-Sprint merger will increase inequality," 11 Feb. 2020 The full extent of the outbreak remains hard to ascertain, in part due to political considerations. Adam Taylor, Washington Post, "Live updates: Coronavirus death toll tops 3,000 in China as global costs mount," 5 Mar. 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

23 May 2020

Cite this Entry

“Ascertain.” Dictionary, Merriam-Webster, Accessed 4 Jun. 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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