unknown

1 of 2

adjective

un·​known ˌən-ˈnōn How to pronounce unknown (audio)
: not known or not well-known
also : having an unknown value
an unknown quantity

unknown

2 of 2

noun

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

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.
Recent Examples on the Web
Adjective
Since the case was kept sealed, Morrissey’s arguments to stop the network from airing the title remained unknown. Winston Cho, The Hollywood Reporter, 14 Mar. 2024 Walmart cashews recalled due to allergy risk Walmart cashews recalled due to allergy risk 00:25 Cashews sold by Walmart in 30 states and on their website have been recalled due to unknown milk and coconut allergens, according to a company statement posted by the U.S. Food and Drug Administration. Alex Sundby, Cara Tabachnick, CBS News, 14 Mar. 2024 One of the ways the federal evidence in this case could complicate matters for the state prosecutor is if those records contain previously unknown instances of contradictory statements or falsehoods by any of the witnesses. Devlin Barrett, Washington Post, 14 Mar. 2024 The economy stopped feeling like a precision machine in need of a tuneup, pointed surely toward growth, and started feeling more like an unpredictable journey to an unknown shore. Sam Dean, Los Angeles Times, 13 Mar. 2024 The specifics of the forthcoming series remain unknown, but both Ghost and Tommy’s stories have already been expanded upon since the conclusion of Power in 2020. Julia Moore, Peoplemag, 13 Mar. 2024 Phil Krinsky, a spokesperson for Phoenix police, said officers were called to an apartment complex near 3rd and McKinley streets after 12 p.m. due to an unknown trouble call. Dylan Wickman, The Arizona Republic, 11 Mar. 2024 However, since the study was conducted with mice, whether these findings apply to humans is unknown. Barbie Cervoni, Verywell Health, 11 Mar. 2024 One of the clowns, a teen-age girl waddling about in a penguin suit, produced a hula hoop, a device heretofore unknown in Al-Hol. Anand Gopal, The New Yorker, 11 Mar. 2024
Noun
Even so, many unknowns surround the story; Herodotus’s description is vaguely worded, and historians doubt that Thales had a deep enough knowledge of astronomy to make a precise prediction. Dan Falk, Smithsonian Magazine, 13 Mar. 2024 While both the Writers Guild of America and SAG-AFTRA were able to secure protections against the technology in their contracts with studios, there are still many unknowns about what the future of AI looks like. Carly Thomas, The Hollywood Reporter, 25 Feb. 2024 With many unknowns still looming, electric vehicles are the future and the future is now. James Raia, The Mercury News, 18 Feb. 2024 That’s what happened with the likes of Chris Rock, Liam Neeson, Julia Roberts and Tim Robbins, who were relative unknowns before Timmermann found roles that helped put them on the path to stardom. Jazz Tangcay, Variety, 14 Feb. 2024 For scientists, there are still many unknowns about how storms and flood risks will evolve as temperatures rise. Ian James, Los Angeles Times, 8 Feb. 2024 Push independent voters to turn out on Tuesday A significant unknown for Haley leading into the Tuesday primary is how many of her new supporters are motivated to cast ballots. USA TODAY, 22 Jan. 2024 Now, as the war enters its third year, leaders in Kyiv are trying to find a new path forward amid ferocious Russian assaults, while facing a series of daunting unknowns. Marc Santora, New York Times, 24 Feb. 2024 There are still a lot of unknowns, and a police investigation is ongoing. Jo Yurcaba, NBC News, 23 Feb. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'unknown.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

Adjective

14th century, in the meaning defined above

Noun

1597, in the meaning defined at sense 1

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

Dictionary Entries Near unknown

Cite this Entry

“Unknown.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unknown. Accessed 28 Mar. 2024.

Kids Definition

unknown

1 of 2 adjective
un·​known ˌən-ˈnōn How to pronounce unknown (audio)
: not known
also : having an unknown value
an unknown quantity

unknown

2 of 2 noun
1
: something that is unknown
2
: a symbol (as x, y, or z) representing a quantity whose value is unknown
an equation with two unknowns

More from Merriam-Webster on unknown

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