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Synonyms

unknown

American  
[uhn-nohn] / ʌnˈnoʊn /

adjective

  1. not known; not within the range of one's knowledge, experience, or understanding; strange; unfamiliar.

  2. not discovered, explored, identified, or ascertained.

    the unknown parts of Antarctica.

  3. not widely known; not famous; obscure.

    an unknown writer.


noun

  1. 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.

  2. 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.

unknown British  
/ ʌnˈnəʊn /

adjective

  1. not known, understood, or recognized

  2. not established, identified, or discovered

    an unknown island

  3. not famous; undistinguished

    some unknown artist

  4. a person or thing whose action, effect, etc, is unknown or unpredictable

"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

noun

  1. an unknown person, quantity, or thing

  2. 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 equation

    3y = 4x + 5 is an equation in two unknowns

"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

Other Word Forms

  • unknownness noun

Etymology

Origin of unknown

First recorded in 1250–1300, unknown is from the Middle English word unknow(e)n. See un- 1, known

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Portuguese former Aalesunds forward Braga is emblematic of Hearts' season - a relative unknown plucked from Norwegian football.

From BBC

With her list of unknowns complete, Adhikari and her husband each brought their laptops to a coffee shop in January.

From The Wall Street Journal

The extent of any casualties or injuries are unknown at this point.

From BBC

The BBC has made multiple attempts to contact Stern, and his current whereabouts are unknown.

From BBC

A large part of the appeal of micro-dramas is seeing and interacting with real actors, she said, because the actors are often unknown and, therefore, accessible on social media.

From BBC