ascertain

[ as-er-teyn ]

verb (used with object)

1. to find out definitely; learn with certainty or assurance; determine:

   to ascertain the facts.

2. Archaic. to make certain, clear, or definitely known.

ascertain

/ ˌæsəˈteɪn /

verb

1. to determine or discover definitely
2. archaic.
   to make certain

Derived Forms

• ˌascerˈtainable, adjective
• ˌascerˈtainment, noun
• ˌascerˈtainably, adverb

Other Words From

• ascer·taina·ble adjective
• ascer·taina·bly adverb
• ascer·tainer noun
• ascer·tainment noun
• nonas·cer·taina·ble adjective
• nonas·cer·taina·ble·ness noun
• nonas·cer·taina·bly adverb
• nonas·cer·tainment noun
• preas·cer·tain verb (used with object)
• preas·cer·tainment noun
• unas·cer·taina·ble adjective
• unas·cer·taina·bly adverb
• unas·cer·tained adjective
• well-ascer·tained adjective

Word History and Origins

Origin of ascertain¹

First recorded in 1400–50; late Middle English, variant of acertain, assertain, from Middle French acertain-, stem of acertener “to make certain”; equivalent to a- ⁵ + certain

Word History and Origins

Origin of ascertain¹

C15: from Old French acertener to make certain

Example Sentences

The adversarial system—in which two parties with opposing interests argue against each other—is hailed from the first year of law school as the ultimate way to ascertain the truth.

From Slate

No one serious about facts would receive a text message of dubious veracity and blast it out to millions to ascertain its accuracy.

From Slate

On September 9, a staffer working for GOP vice presidential nominee JD Vance contacted the city manager of Springfield, Ohio, to ascertain the truth around rumors of Haitian immigrants eating local pets, only to be told that such claims were entirely baseless, according to a Wall Street Journal report.

From Salon

In her post-debate reaction, MSNBC’s Rachel Maddow repeated the wisdom many TV experts have shared about debates, which is that you can ascertain all you need to know with the sound off.

From Salon

It is impossible to ascertain the exact number of babies they may have killed, given the way the data was gathered.

From BBC

Related Words

• confirm
• determine
• divine
• double-check
• find out
• verify