Dictionary.com
definitions
  • synonyms

unknown

[uhn-nohn]
See more synonyms for unknown on Thesaurus.com
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.
Show More
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.
Show More

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. 2018

Examples from the Web for unknown

Contemporary Examples

Historical Examples

  • A few years only back, every Carolinian rode to town, and the motor was unknown.

    'Tis Sixty Years Since

    Charles Francis Adams

  • "And they come from a bitter heart," answered the unknown knight.

    The White Company

    Arthur Conan Doyle

  • Then he was but a penniless, monk-bred lad, unknown and unfriended.

    The White Company

    Arthur Conan Doyle

  • Like the Admirable Crichton, no art is to her unknown, no accomplishment by her neglected.

  • It is merely a case of not liking him less, but of liking my unknown man more.

    Her Father's Daughter

    Gene Stratton-Porter

British Dictionary definitions for unknown

unknown

adjective
  1. not known, understood, or recognized
  2. not established, identified, or discoveredan unknown island
  3. not famous; undistinguishedsome unknown artist
  4. unknown quantity a person or thing whose action, effect, etc, is unknown or unpredictable
Show More
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 equation3y = 4x + 5 is an equation in two unknowns
Show More
Derived Formsunknownness, 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

Word Origin and History for unknown

adj.

c.1300, "strange, unfamiliar" (of persons, places), from un- (1) "not" + past participle of know. Cf. Old English ungecnawen. In reference to facts, attested from early 14c. The noun meaning "unknown person" is recorded from 1590s.

Show More
Online Etymology Dictionary, © 2010 Douglas Harper