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

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 But the last paragraph of the 11-page bill, approved earlier this month apparently unbeknownst to even Edsall’s attorneys, has nothing to do with data storage. Dave Altimari, courant.com, "Amendment To Unrelated Law Could Help UConn Coach Edsall's Son Keep Job," 25 June 2018 So is Woodstock itself, since Pearl and Alison, unbeknownst to the other, both run off to the festival. Jessica Zack, San Francisco Chronicle, "Diane Lane-Viggo Mortensen film ‘A Walk on the Moon’ on the musical stage," 6 June 2018 And completely unbeknownst to us, last week, a large consumer search engine picked that up. Recode Staff, Recode, "Full transcript: Matt Cutts of the U.S. Digital Service on Recode Decode," 12 July 2018 There weren’t any movies on the plane, but Blair had Wifi—and two apparent lovebirds who, unbeknownst to them, had just gone viral. Emma Stefansky, Vanities, "Not Everyone Thinks That Viral Airplane Matchmaker Thread Is Cute," 5 July 2018 On the road in Jack’s old Rolls-Royce for much of the movie, Jack wastes no time enlisting Henry, unbeknownst to his mom, to help him sell his marijuana stash. Jessica Zack, SFChronicle.com, "Christopher Plummer quite a character actor in ‘Boundaries’," 20 June 2018 Tell-tale Scars Even as Scherer, Tulaczyk and their colleagues grappled with these surprises, another scientist, unbeknownst to them, was making his own discovery. National Geographic, "The West Antarctic Ice Sheet Seems to Be Good at Collapsing," 13 June 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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Phrases Related to unbeknownst

unbeknown to

unbeknownst to

Statistics for unbeknownst

Last Updated

8 Oct 2018

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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

Comments on unbeknownst

What made you want to look up unbeknownst? Please tell us where you read or heard it (including the quote, if possible).


exaggeratedly or childishly emotional

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