[ uhn-nohn ]
/ ʌnˈnoʊn /
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See synonyms for: unknown / unknowns on Thesaurus.com


not known; not within the range of one's knowledge, experience, or understanding; strange; unfamiliar.
not discovered, explored, identified, or ascertained: the unknown parts of Antarctica.
not widely known; not famous; obscure: an unknown writer.


a thing, influence, area, factor, or person that is unknown: the many unknowns in modern medicine; The director cast an unknown in the leading role.
Mathematics. a symbol representing an unknown quantity: in algebra, analysis, etc., frequently represented by a letter from the last part of the alphabet, as x, y, or z.



Set some time apart to test your bracket symbol knowledge, and see if you can keep your parentheses, squares, curlies, and angles all straight!
Question 1 of 7
Let’s start with some etymology: What are the origins of the typographical word “bracket”?

Origin of unknown

First recorded in 1250–1300, unknown is from the Middle English word unknow(e)n.See un-1, known
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

Example sentences from the Web for unknown

British Dictionary definitions for unknown

/ (ʌnˈnəʊn) /


not known, understood, or recognized
not established, identified, or discoveredan unknown island
not famous; undistinguishedsome unknown artist
unknown quantity a person or thing whose action, effect, etc, is unknown or unpredictable


an unknown person, quantity, or thing
maths a variable, or the quantity it represents, the value of which is to be discovered by solving an equation; a variable in a conditional equation3y = 4x + 5 is an equation in two unknowns

Derived forms of unknown

unknownness, noun
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
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