unknown

adjective
un·​known | \ ˌən-ˈnōn How to pronounce unknown (audio) \

Definition of unknown

 (Entry 1 of 2)

: not known or not well-known also : having an unknown value an unknown quantity

unknown

noun

Definition of unknown (Entry 2 of 2)

1 : one that is not known or not well-known especially : a person who is little known (as to the public)
2 : something that requires discovery, identification, or clarification: such as
a : a symbol (such as x, y, or z) in a mathematical equation representing an unknown quantity
b : a specimen (as of bacteria or mixed chemicals) required to be identified as an exercise in appropriate laboratory techniques

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Synonyms for unknown

Synonyms: Adjective

unbeknownst (also unbeknown)

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Examples of unknown in a Sentence

Adjective

a disease of unknown cause Much remains unknown about his early life. Her music was previously unknown outside of Asia. An unknown number of cases go unreported. The victim's attacker was unknown to her. For some unknown reason, my computer crashed. a book of unknown poems

Noun

explorers venturing off into the unknown A fear of the unknown kept her from changing jobs. The director cast an unknown in the lead role. We're facing too many unknowns.
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Recent Examples on the Web: Adjective

The actors behind these recent incidents are largely unknown. Lily Hay Newman, WIRED, "Ransomware Hits Georgia Courts As Municipal Attacks Spread," 1 July 2019 Investigators also believe that Adams allegedly shot and killed Bracke and Hanen, before returning to his residence with his wife and son inside, but the chronology of events beyond that moment is currently unknown. Joelle Goldstein, PEOPLE.com, "Calif. Man, His Wife and Son Among 5 Dead After 'Ongoing Dispute' at Mobile Home Park Turns Deadly," 25 June 2019 At the time, Auburn was an unknown too — still suffering through a 14-year NCAA Tournament drought. Sam Blum | Sblum@al.com, al.com, "How Auburn basketball found 2020 commit Justin Powell," 25 June 2019 Brian Chesky, then a relatively unknown entrepreneur, was explaining his business, and Jordan couldn’t help mentally listing the number of risks associated with opening up one’s home to strangers. Polina Marinova, Fortune, "Term Sheet -- Monday, June 24," 24 June 2019 Smailagic wasn’t totally unknown to the league’s scouts, and the Warriors’ work at trying to keep him secret should have alerted the other teams. Scott Ostler, SFChronicle.com, "Warriors’ get their (mystery) man in Alen Smailagic," 20 June 2019 Actress/filmmaker Jodie Foster narrates this eye-opening documentary by Pamela B. Green on a pioneering female filmmaker who was involved in more than 1,000 films but is relatively unknown today. Randy Myers, The Mercury News, "Weekend movies: Woody, Buzz back for ‘Toy Story 4’," 19 June 2019 The woman's suffrage movement spanned decades, but much of that history is widely unknown. Jessie Balmert, Cincinnati.com, "100 years ago Ohio ratified the 19th Amendment. Here are 6 women who made suffrage reality," 14 June 2019 The identity of the attackers is currently unknown. Kyle Mizokami, Popular Mechanics, "Two Oil Tankers Attacked in the Middle East, U.S. Destroyer Rescues Crew," 13 June 2019

Recent Examples on the Web: Noun

But nothing is guaranteed, and an NFL season always includes the unknown. Scott Patsko, cleveland.com, "3 reasons the Browns could miss the playoffs in 2019 (video)," 1 July 2019 So the filmmakers decided to bring back Bonnie, who faces the disorienting unknown of kindergarten orientation day - an event that calls upon Woody's sense of mission. Michael Cavna, Anchorage Daily News, "Why make ‘Toy Story 4’ after a satisfying trilogy? Here’s how the director found his inspiring answer," 20 June 2019 So the filmmakers decided to bring back Bonnie, who faces the disorienting unknown of kindergarten orientation day — an event that calls upon Woody’s sense of mission. Michael Cavna, Washington Post, "Why make ‘Toy Story 4’ after a satisfying trilogy? Here’s how the director found his inspiring answer.," 19 June 2019 Some unknowns about Amazon’s robotics project are questions of economics, not engineering. Tom Simonite, WIRED, "How Amazon Cloned a Neighborhood to Test Its Delivery Robots," 14 June 2019 Horse racing needs to own that and work to remove the sinister aspects that accompany the unknowns. Gentry Estes, The Courier-Journal, "As horses keep dying on the track, the industry is left to answer impossible questions," 13 June 2019 If free agency wasn’t going to be hectic enough, this throws another unknown into the equation. Jeff Zillgitt, USA TODAY, "How Kevin Durant's injury alters the NBA landscape — this summer and beyond," 11 June 2019 However, there are some unknowns in the multi-male mating hypothesis, notes Craig Packer, director of the Lion Research Center at the University of Minnesota. Grant Currin, National Geographic, "How Asiatic lionesses shield their cubs from killer males," 26 Apr. 2019 Even beyond that, the method that the scientists are using also has some unknowns. Avery Thompson, Popular Mechanics, "Scientists Are Testing a Way to Exterminate Mosquitoes for Good," 20 Feb. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'unknown.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of unknown

Adjective

14th century, in the meaning defined above

Noun

1597, in the meaning defined at sense 1

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Statistics for unknown

Last Updated

5 Jul 2019

Look-up Popularity

Time Traveler for unknown

The first known use of unknown was in the 14th century

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More Definitions for unknown

unknown

adjective

English Language Learners Definition of unknown

 (Entry 1 of 2)

: not known
: not well-known : not famous

unknown

noun

English Language Learners Definition of unknown (Entry 2 of 2)

: a place, situation, or thing that you do not know about or understand
: a person who is not famous or well-known
: something that is not known or not yet discovered

unknown

adjective
un·​known | \ ˌən-ˈnōn How to pronounce unknown (audio) \

Kids Definition of unknown

 (Entry 1 of 2)

: not known … it was cut all over with strange lines and figures that might be the letters of an unknown language.— C. S. Lewis, The Lion, the Witch and the Wardrobe

unknown

noun

Kids Definition of unknown (Entry 2 of 2)

: one (as a quantity) that is unknown

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More from Merriam-Webster on unknown

Rhyming Dictionary: Words that rhyme with unknown

Thesaurus: All synonyms and antonyms for unknown

Spanish Central: Translation of unknown

Nglish: Translation of unknown for Spanish Speakers

Britannica English: Translation of unknown for Arabic Speakers

Comments on unknown

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