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

That person’s condition is unknown at this time, Vick said. Ivana Hrynkiw | Ihrynkiw@al.com, al.com, "Walker County wreck leaves four dead, one injured," 11 July 2019 The extent of Epstein's relationship with Andrew or other members of the royal family is also unknown, though the two men were photographed walking together in Central Park in 2010 (above), several years after Epstein was released from prison. Caroline Hallemann, Town & Country, "The Royal Family's Troubling Connection to Jeffrey Epstein," 10 July 2019 His work suggested that leaders could be flawed and misguided, villains could be human, and answers could be unknown. Masha Gessen, The New Yorker, "The Beautiful Uncertainty of Douglas Crimp," 9 July 2019 Shared widely on the internet and in virtually every DIY beeswax book, its origins are unknown. Gemma Tarlach, Milwaukee Journal Sentinel, "Bounty of the bees extends far beyond honey for your tea - to lotions, balms and even drinks," 16 July 2019 The child's condition is unknown, according to a Cincinnati Fire Department Twitter account. Rachel Berry, Cincinnati.com, "9-year-old boy pulled from Mill Creek has died," 16 July 2019 The effects of methamphetamine on alligators is unknown. Kristin Lam, USA TODAY, "Methed-up gators and ducks and geese, oh my! Tennessee police warn against flushing drugs down the toilet," 15 July 2019 Though the full impact of dysbiosis is still unknown, Cook said there are a variety of symptoms that can occur because of the condition. Texas A&m University, Houston Chronicle, "Pet Talk: The benefits of a balanced microbiome," 13 July 2019 The motive for the shooting is unknown, police said, and no suspects have been identified. Paul Cobler, Dallas News, "Killer at large after 22-year-old woman found shot in car in east Oak Cliff," 13 July 2019

Recent Examples on the Web: Noun

One unknown is the future of Paul Achleitner, who has been the chairman of Deutsche Bank’s supervisory board since 2012 and is blamed by some investors and executives for the bank’s fall from grace. David Enrich, New York Times, "Deutsche Bank, in a Last-Ditch Effort to Stop Its Spiral, Could Lay Off 20,000," 28 June 2019 The biggest unknown is the outcome of a potential China trade deal. NBC News, "If the Fed cuts rates this year, it won't be because Trump asked," 13 June 2019 Whether that extends to gaming laptops—particularly high-end ones—anytime soon is an unknown. Gordon Mah Ung, PCWorld, "Why you should or shouldn't buy a GeForce RTX laptop," 6 Mar. 2019 Another unknown is how the largest investors will behave. Nicole Friedman, WSJ, "Insurers Push Back Against Paying More for Their Own Insurance," 2 Jan. 2019 The biggest unknown is what the world will actually do to address climate change. Umair Irfan, Vox, "Winters are warming faster than summers. These US cities could lose weeks of freezing days by 2050.," 21 Dec. 2018 Those pieces all look promising, but the unknown is how Mahomes will fare as a leader and in handling all the nuances of playing quarterback. Lindsay H. Jones, USA TODAY, "Chiefs training camp questions: Can Patrick Mahomes take Kansas City to next level?," 2 July 2018 The unknown is what terms Joshua has offered to Wilder (40-0, 39 KOs) after Wilder’s team previously extended a $50 million guarantee for Joshua to fight in the U.S. Lance Pugmire, latimes.com, "Deontay Wilder mulling offer to fight Anthony Joshua, official says," 20 June 2018 For senior Makensie Neville, the unknown is inevitable. Jennie Key, Cincinnati.com, "Last curtain call: Final play at Mercy High School is bittersweet," 3 May 2018

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

19 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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an act or instance of editing or removing

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