ascertain

verb as·cer·tain \ ˌa-sər-ˈtān \

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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ascertainable

play \-ˈtā-nə-bəl\ adjective

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ascertainment

play \-ˈtān-mənt\ noun

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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

Recent Examples of ascertain from the Web

Further, if the marijuana on the defendant’s possession had been packaged for sale and distribution and if significant amounts of cash were also found, jurors would have additional clues in ascertaining the defendant’s intent.

— michael mccann, SI.com, "The Potential Fallout From Zach Randolph's Marijuana-Related Arrest," 10 Aug. 2017
An MIT page created for the project allows users to input any sentence and submit it to DeepMoji, which then ascribes five emojis to ascertain the emotions behind the sentence.

— max londberg, kansascity, "Machine brain that learns from emojis detects sarcasm better than humans," 9 Aug. 2017
As one might ascertain, the whole thing is pretty terrible.

— ashley edwards walker, Glamour, "This Viral Anti-Diversity Memo by a Google Employee Just Got Shut Down," 6 Aug. 2017
These clues helped Siver ascertain that at one point, winters in Canada's northwest never fell below freezing.

— matt ormseth, courant.com, "Conn College Professor Wins New Grant To Study Mystery Of Canada’s Prehistoric Tropical Climate," 3 Aug. 2017
A driver-facing camera mounted on the instrument panel uses gaze-tracking to ascertain if the driver is actually paying attention.

— jonathan m. gitlin, Ars Technica, "Bosch took us for a ride in its level 3 autonomous car," 18 July 2017
Upon receiving the certificate, the browser will reach out to one of these services and perform the necessary query to ultimately ascertain the status of the certificate.

— scott helme, Ars Technica, "HTTPS Certificate Revocation is broken, and it’s time for some new tools," 3 July 2017
Bryce Heinlein said investigators were still trying to ascertain the cause of the man’s injuries.

— sacbee, sacbee.com, "Dead man found on midtown Sacramento sidewalk identified," 30 June 2017
Whether or not the issues of those pitchers is attributable definitively to the WBC is hard to ascertain, of course.

— larry stone, The Seattle Times, "Hardly world-beaters: World Baseball Classic seems to be at least partially responsible for struggles of Mariners pitchers.," 29 June 2017

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.

Origin and Etymology of ascertain

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

NEW! Time Traveler

First Known Use: 15th century

See Words from the same year

ascertain Synonyms

Synonyms

discover, catch on (to), find out, get on (to), hear, learn, realize, see, wise (up)

Antonyms

miss, overlook, pass over

Related Words

hit (on or upon), tumble (to); descry, detect, encounter, espy, see, spot; calculate, dope (out), figure out, find, puzzle (out); discern, mind, note, observe, perceive; divine

Near Antonyms

miss, overlook; disregard, ignore; forget, unlearn; blanket, blot out, cloak, conceal, cover, curtain, enshroud, hide, mask, occult, screen, shroud, veil

Synonym Discussion of 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.