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

Lili Reinhart and Keke Palmer are also involved, though their character names are unknown. Christopher Rosa, Glamour, "Everything We Know About Jennifer Lopez and Lili Reinhart’s New Movie Hustlers," 16 Apr. 2019 The fate of some paintings inside the structure and its three famous rose windows is still unknown. Steff Yotka, Vogue, "Fashion Luxury Groups, Kering and LVMH, Pledge Combined 300 Million Euros to Repair Notre Dame," 16 Apr. 2019 At the conclusion of season one, the fate of Ruby Martinez, portrayed by actor Jason Genao, was unknown. Lauren Rearick, Teen Vogue, ""On My Block" Season 2 Teaser Video and First Look Photos Hint That Ruby Is Still Alive," 7 Mar. 2019 The name and scent of the new perfume is unknown, but the bottle is fittingly shaped like a giant pair of pink lips (duh). Jenna Rosenstein, Harper's BAZAAR, "Kylie Jenner's First Perfume Is Shaped Like Giant Lips," 1 Apr. 2019 While Deepak Ahuja’s motives are unknown, the fact that Tesla is trying to fund its lofty ambitions on the cheap certainly may have contributed to workplace stress. Charley Grant, WSJ, "Tesla: Champagne Dreams on a Six-Pack Budget," 31 Jan. 2019 The cause is unknown, but cluster headaches may occur if something with the body’s biological clock is off, per the Mayo Clinic. Amy Marturana, SELF, "What Your Headaches Can Tell You About Your Health," 29 Dec. 2018 Although many details of the project are still unknown, here’s what’s been made public about the project so far, and some important history around it. Shirin Ghaffary, Recode, "Everything you need to know about Google’s controversial China plans in advance of today’s congressional hearing," 11 Dec. 2018 And here was a character whose goals had to remain unknown, who was mysterious even to the people who knew him best. Adam Rathe, Town & Country, "What Making The Front Runner Taught Director Jason Reitman About Politics and Privacy," 21 Nov. 2018

Recent Examples on the Web: Noun

This is fine and all, but as every person and doll knows, time is a single-lane freeway hurtling us toward the unknown, or to a landfill outside Albany. Brennan Kilbane, Allure, "Barbie's 60th Birthday Wish Was to Be More Inclusive. Now What?," 2 May 2019 What's scary about affairs is there's a lot of unknowns. Meredith Clark, SELF, "Why Some Couples Can Recover After Cheating and Others Can't," 27 Dec. 2018 Here are my best tips for moving beyond the fear of the unknown and making your big dreams a reality. 1. SELF, "6 Tips for Pushing Fear Aside So You Can Finally Reach Your Fitness Goals," 31 Oct. 2018 Perhaps the most difficult thing about traveling with diabetes is a fear of the unknown. Christopher Elliott, chicagotribune.com, "For people with diabetes, air travel can present a host of challenges," 12 July 2018 Whether its day to day engagement, networking, conflict resolution or strategic planning, candid feedback and humble acknowledgement of the unknown, are valued and promoted. Fortune, "Synchrony Financial," 26 June 2018 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

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

26 Apr 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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one that collects or salvages junk

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