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unbeknown

[ uhn-bi-nohn ]
/ ˌʌn bɪˈnoʊn /

adjective

unknown; unperceived; without one's knowledge (usually followed by to).

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You may have read the word "simmer" in a recipe or two, but what does it really mean?
To cook in water that begins cold and then reaches a boil.
To stew in a sauce for a long time.
To cook in water, just below boiling temperature.
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Also un·be·knownst [uhn-bi-nohnst]. /ˌʌn bɪˈnoʊnst/.

Origin of unbeknown

1630–40; un-1 + beknown (late Middle English beknowe, past participle of beknowen); see be-, known
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for unbeknown

British Dictionary definitions for unbeknown

unbeknown
/ (ˌʌnbɪˈnəʊn) /

adverb

(sentence modifier foll by to) without the knowledge (of a person)unbeknown to him she had left the country Also (esp Brit): unbeknownst

adjective

(postpositive usually foll by to) rare not known (to)

Word Origin for unbeknown

C17: from the archaic beknown known; see be-, know
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012