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

But because there is still a lot unknown about the disease, some experts believe the issue warrants caution—especially for those who consume meat from those animals. Korin Miller, SELF, "What You Need to Know About So-Called 'Zombie' Deer Disease," 20 Feb. 2019 An unknown number of Tibetans were killed by security forces in the aftermath. Christopher Bodeen, The Seattle Times, "China closes Tibet to foreigners for sensitive anniversaries," 19 Feb. 2019 The characters, night crawlers, really, are observed surreptitiously advancing to an unknown destination, their motivation unclear. Vogue, "If You Loved The OA, You'll Love Vince's New Film for Spring ’19," 5 Feb. 2019 That’s unknown but having what amounts to a third player in sound cards can only be good for PC audio ,which has always played second fiddle to sexier graphics cards, CPUs, and even storage. Gordon Mah Ung, PCWorld, "EVGA gets into sound cards with Nu Audio, a high-end board that delivers 'lifelike' gaming," 8 Jan. 2019 And there are plenty of bigger — and therefore more dangerous — space rocks cruising around out there in the dark depths, the vast majority of them unseen and unknown. Mike Wall, Space.com, "Asteroid Billiards: This Wild Idea to Protect Earth Just Might Work," 24 Aug. 2018 Two unknown suspects stole multiple clothing items valued at $250 from Old Navy, 417 N. Harlem Ave. Staff Report, chicagotribune.com, "Police: Oak Park resident robbed while walking on Austin Boulevard," 14 July 2018 Ross was still an unknown painter traveling in his Datsun motor home, filled with paints, canvases and brushes. Julia Lyon, Washington Post, "People are waiting in line. Is it Hamilton? No, it’s Bob Ross on YouTube.," 13 July 2018 Authorities released the name Friday of an inmate who died of unknown causes this week at the Vista Detention Facility. City News Service, sandiegouniontribune.com, "Inmate who died at Vista jail ID'd," 13 July 2018

Recent Examples on the Web: Noun

For too many of us, comfort kills curiosity and the familiar trumps the unknown, authenticity be damned. Steve Lopez, latimes.com, "A beloved taco joint run by an 81-year-old matriarch may get crushed to make way for Chipotle," 5 May 2018 Fear of the unknown has given way to a certain fatigue. Amy Verner, Vogue, "First Dior Men, Now Thom Browne—The Gilets Jaunes Are Impacting the Fall ’19 Paris Men’s Shows," 9 Jan. 2019 Second, for the buyer, there is a fear of the unknown. Anchorage Daily News, "The age of your house isn’t just about the year it was built. Here’s why that’s important when you’re selling.," 22 June 2018 The scariest thing is the anticipation of the unknown. Chelsey Lewis, Milwaukee Journal Sentinel, "Whitewater rafting on the Wolf River is a wild thrill," 14 June 2018 And perhaps the most important of all the unknowns, what will the bride wear? Carrie Goldberg, Harper's BAZAAR, "What Princess Eugenie Will Likely Wear to Her Wedding Reception is #GOALS," 3 Oct. 2018 Detection is far less likely, however, because few people recognize the unknowns, or care about their times. Dennis Wagner, azcentral, "Phoenix man's questionable marathon times draw him into debate on amateur cheating," 11 May 2018 Of the unknowns, all eyes are on a handful of moderate Democrats who Republicans are trying to win over, like Sens. Jeremy Herb, CNN, "Pompeo confirmation winnowing down to a handful of undecided Democrats," 18 Apr. 2018 Two relative unknowns -- industrialist Alan Kestenbaum and Ben Navarro, founder of Sherman Financial Group LLC -- have each proposed more than that amount, while hedge fund titan David Tepper submitted a bid that is reportedly lower. Bloomberg.com, "Bashful Billionaires Battle to Own NFL Team," 12 Apr. 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

15 Mar 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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the range of authority or knowledge

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