un·​be·​knownst | \ ˌən-bi-ˈnōn(t)st \
variants: or less commonly unbeknown \ ˌən-​bi-​ˈnōn \

Definition of unbeknownst

1 : happening or existing without the knowledge of someone specified usually used with to unbeknownst to us rumors were flying
2 : unknown

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Synonyms for unbeknownst



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Did You Know?

Unbeknownst derives from beknown, an obsolete synonym of known. But for a word with a straightforward history, unbeknownst and its older and less common variant unbeknown have created quite a flap among usage commentators. Despite widespread use (including appearances in the writings of Charles Dickens, A.E. Housman, and E.B. White), the two words have been called everything from "obsolete" to "vulgar." Our evidence, however, shows that both can be considered standard.

Examples of unbeknownst in a Sentence

unbeknownst to me, my mother was planning a party

Recent Examples on the Web

When companies—unbeknownst to city officials—introduced dockless bikes and scooters to streets, local officials have often responded with bans to rein in the activities of users. Megan Barber, Curbed, "The weirdest places we found scooters in 2018," 21 Dec. 2018 Mixed up In an experiment at Tufts, white students were prompted to talk about campus diversity with a racially ambiguous student who, unbeknownst to them, was scripted by the psychologists. Kevin Lewis, BostonGlobe.com, "Selling distrust," 11 May 2018 As the temperatures in the California desert climb near 100 degrees, Goldsmith and his parents stick close to the shade of Guy’s Stagecoach Smokehouse, sampling the offerings, waiting — unbeknownst to him — to meet and cook with his idol. Gerrad Hall, EW.com, "Watch Guy Fieri surprise super fan who won Chopped Junior and beat cancer three times," 10 May 2018 Their relationship began back when Ralph Lauren invited them to attend the 2017 Met Gala in New York together—unbeknownst to him, the two had been flirting over text for quite some time before this. Vogue, "Priyanka Chopra and Nick Jonas Are Married—And the Newlyweds Are the Stars of Vogue’s First Digital Cover," 1 Dec. 2018 Only a portion was removed, unbeknownst to me until two years later. Jacqueline Andriakos, SELF, "What Appendicitis Really Feels Like, From 13 People Who Have Been There," 16 Oct. 2018 The pair alleged that, unbeknownst to them, Biffle had recorded them with cameras wired in the master bedroom, bathroom, and a guest room, of the couple’s North Carolina home, the Charlotte Observer reported. Elizabeth Zwirz, Fox News, "Ex-NASCAR driver Greg Biffle ordered to pay ex-wife $1 for personal recordings, jury decides," 14 Aug. 2018 Apparently the film students were shooting a homework project at a property in Guadalajara, which, unbeknownst to them, was a cartel safe house. Mike Miller, PEOPLE.com, "Guillermo del Toro Mourns Three Film Students 'Killed and Dissolved in Acid' by a Mexican Cartel," 25 Apr. 2018 Her parents wanted her to be a teacher, and unbeknownst to them, Modersohn-Becker’s works would go on to teach and inspire scholars and artists for generations to come. National Geographic, "These Famous Women Artists Changed the World With Their Self-Portraits," 24 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'unbeknownst.' 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 unbeknownst

1636, in the meaning defined at sense 1

History and Etymology for unbeknownst

un- entry 1 + obsolete English beknown known; unbeknownst, irregular from unbeknown

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Last Updated

29 Jan 2019

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Time Traveler for unbeknownst

The first known use of unbeknownst was in 1636

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More Definitions for unbeknownst


un·​be·​knownst | \ ˌən-bi-ˈnōnst \
variants: also unbeknown \ -​ˈnōn \

Kids Definition of unbeknownst

: happening without someone's knowledge : unknown Unbeknownst to him, we were planning a surprise party.

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More from Merriam-Webster on unbeknownst

Thesaurus: All synonyms and antonyms for unbeknownst

Spanish Central: Translation of unbeknownst

Nglish: Translation of unbeknownst for Spanish Speakers

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