un·​be·​knownst ˌən-bi-ˈnōn(t)st How to pronounce unbeknownst (audio)
variants or less commonly unbeknown
: happening or existing without the knowledge of someone specified
usually used with to
unbeknownst to us rumors were flying

Did you know?

Unbeknownst is an irregular variant of the older unbeknown, which derives from beknown, an obsolete synonym of known. But for a word with a straightforward history, unbeknownst and the now less common unbeknown have caused quite a stir among usage commentators. In spite of widespread use (including appearances in the writings of Charles Dickens, A. E. Housman, and E. B. White), the grammarian H. W. Fowler in 1926 categorized the two words as "out of use except in dialect or uneducated speech." The following year, G. P. Krapp called them "humorous, colloquial, and dialectal." Our evidence, however, shows that both words are standard even in formal prose.

Examples of unbeknownst in a Sentence

unbeknownst to me, my mother was planning a party
Recent Examples on the Web Reportedly, unbeknownst to Eastwood himself, director Petersen told Rene Russo to gently grab the actor’s hand off-camera during a key point in the monologue, which prompted this rare display of real emotion. Vulture, 19 Aug. 2022 In fact, unbeknownst to scientists until recently, ancient cities also dealt with toxic pollution; and the blooms may even have contributed to the eventual demise of civilizations. Marisa Sloan, Discover Magazine, 18 Apr. 2022 Raymond Lee stars in the series as Dr. Ben Song, a physicist on the Quantum Leap project who, unbeknownst to his fellow team members, has upgraded the Quantum Leap accelerator and sends himself back in time and into the bodies of people in the past. Rick Porter, The Hollywood Reporter, 12 Dec. 2022 She is joined once again by her Gen Z writing partner Ava Daniels (Hannah Einbinder), who — unbeknownst to Deborah — got drunk and sent a nasty email about Deborah to some equally nasty producers. Karla Peterson, San Diego Union-Tribune, 30 Sep. 2022 Whitley never performed at the CMA Awards and never became a member of the Grand Ole Opry (though unbeknownst to him, his Opry invitation was set for three weeks after his passing). Jessica Nicholson, Billboard, 17 May 2022 McGhehey also has a fake beard glued to his face made (unbeknownst to him) of the cast and crew’s collective pubic hair. Vulture, 1 Feb. 2022 That night, Elizabeth and her sister Leslie came home and spent time on the lower level of their parent’s home heading upstairs where, unbeknownst to them, Carney was lying in wait with a handgun. Taylor Hartz, Hartford Courant, 31 Jan. 2023 Unfortunately, history was almost erased as this devastating tragedy was unbeknownst to many for nearly six decades. Rayna Reid Rayford, Essence, 10 Jan. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'unbeknownst.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


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

First Known Use

1636, in the meaning defined at sense 1

Time Traveler
The first known use of unbeknownst was in 1636


Dictionary Entries Near unbeknownst

Cite this Entry

“Unbeknownst.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unbeknownst. Accessed 26 Feb. 2024.

Kids Definition


un·​be·​knownst ˌən-bi-ˈnōn(t)st How to pronounce unbeknownst (audio)
variants also unbeknown
: happening without one's knowledge : unknown
events unbeknownst to me

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