as·​cer·​tain | \ˌa-sər-ˈtān \
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 \ adjective
ascertainment \-​ˈtān-​mənt \ 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

Facebook executives said today that the company wasn’t able to ascertain the motives of the bad actors. Theodore Schleifer, Recode, "Iran — not just Russia — is trying to influence through Facebook," 22 Aug. 2018 The extensive treatment of paintings, prints and the ways of ascertaining authenticity would profit from more images. Willard Spiegelman, WSJ, "‘The Eye’ Review: Arbiters of the Authentic," 9 Aug. 2018 Normally, such personalization raises privacy concerns because effective personalization requires the tracking of personal preferences and habits to ascertain what things a person is likely to be interested in. Peter Bright, Ars Technica, "Firefox will show sponsored content that’s personalized but private," 1 May 2018 Tobin-Presser asked for communications surrounding the loan documents to ascertain why these debts were paid by the Alaska Dispatch and not from Rogoff's personal accounts. Author: Naomi Klouda, Anchorage Daily News, "Judge gives OK for trustee to examine Rogoff finances," 25 Jan. 2018 The outlines seem to trail and cross from figure to figure — sometimes impossible to ascertain where one body ends and another begins. Sharon Mizota,, "Black and gay: Jonathan Lyndon Chase's paintings play with cultural conventions," 25 June 2018 That’s not all: Hubble has made some pretty astounding discoveries, from ascertaining the age of the universe to finding new moons for Pluto. Michael Hardy, WIRED, "Space Photos of the Week: Light a Candle for Hubble, Still Gazing Strong," 21 Apr. 2018 With one phone call—or even a cursory glance at a media guide—Newton could easily have discerned the identity of the scout and ascertained for himself whether Richardson had, in fact, used racial epithets. Jon Wertheim,, "The Striking Contrast Between the Mavs and Panthers In Crisis," 23 Feb. 2018 Here are some tips for businesses: ▪ Audit your website to ascertain what potential barriers to access may be present. Carol Lumpkin And Stephanie Moot, miamiherald, "Is your website ADA-compliant? Avoid becoming a litigation target," 25 June 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

22 Nov 2018

Look-up Popularity

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 \
ascertained; ascertaining

Kids Definition of ascertain

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

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