unknown

[uhn-nohn]

SEE MORE SYNONYMS FOR unknown ON THESAURUS.COM

adjective

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.

noun

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.

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. 2019

Related Words for unknown

unexplored, exotic, unidentified, remote, undiscovered, unfamiliar, foreign, strange, anonymous, new, nameless, unnamed, uncharted, unexplained, unrecognized, dark, alien, far, secret, so-and-so

Examples from the Web for unknown

Contemporary Examples of unknown

While Faal and Njie are in U.S. custody, the whereabouts of the other survivors is unknown.
The Shadowy U.S. Veteran Who Tried to Overthrow a Country
Jacob Siegel
January 6, 2015
The police suspect that the other unaccounted for 643,000 bitcoins, were removed from customer accounts via an unknown party.
Japanese Bitcoin Heist ‘an Inside Job,’ Not Hackers Alone
Nathalie-Kyoko Stucky, Jake Adelstein
January 1, 2015
Until recently, the hacker collective known as Lizard Squad was all but unknown.
The Attack on the Hidden Internet
Marc Rogers
December 29, 2014
I believe that my case is being interfered with by unknown elements inside Iran.
An American Marine in Iran’s Prisons Goes on Hunger Strike
IranWire
December 18, 2014
We are not concerned or jittered about an unknown candidate.
Liberian Senatorial Elections Defy Ebola
Wade Williams
December 1, 2014

Historical Examples of unknown

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.
The Bacillus of Beauty
Harriet Stark
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

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

noun

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 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.