verb as·cer·tain \ ˌa-sər-ˈtān \
Updated on: 16 Mar 2018

Definition of ascertain

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


play \-ˈtā-nə-bəl\ adjective


play \-ˈtān-mənt\ noun

Examples of ascertain in a Sentence

  1. 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 DreifusNew York Times2 Oct. 2007
  2. 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 HoganTechnology ReviewApril 2002
  3. With an equation linking the money wage to prices, the degree of inflation could be ascertained. —Sidney WeintraubModern Economic Thought(1977) 1993

Recent Examples of ascertain from the Web

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

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.
    • 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

ASCERTAIN Defined for Kids


verb as·cer·tain \ ˌa-sər-ˈtān \

Definition of ascertain for Students

ascertained; ascertaining
: to find out with certainty
  • Police tried to ascertain the cause of the accident.

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