: not known or not well-known
also
: having an unknown value
an unknown quantity
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
Synonyms
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
Dan Brooks, New York Times, 12 Sep. 2023
Its full impact on reservation systems and casino floors in Las Vegas, the company's base, as well as at properties in Maryland, Massachusetts, Michigan, Mississippi, New Jersey, New York and Ohio, was unknown, spokesperson Brian Ahern said.
—Dennis Romero, NBC News, 12 Sep. 2023
The exact number is unknown, but firefighter union leaders say 341 FDNY members have died of illnesses related to 9/11, CBS New York reports.
—CBS News, 11 Sep. 2023
The extent of the injuries was unknown, Deputy Fire Chief Dan Kline told CNN in a phone call.
—Michelle Watson, CNN, 11 Sep. 2023
Amtrak’s exact return date to the Gulf Coast remains unknown, but the Mobile City Council will play a major role in determining the extent of the Port City’s involvement.
—John Sharp | Jsharp@al.com, al, 9 Sep. 2023
The exact cause is unknown, but psoriasis is believed to be related to an immune system malfunction that causes skin cells to grow too quickly, leading to the formation of the scaly patches, and may be triggered by stress, infections, or certain medications, explains Dr. Kamangar.
—Andi Breitowich, Women's Health, 8 Sep. 2023
Those sales also release an unknown amount of weaponry into the world.
—Nick Penzenstadler, USA TODAY, 8 Sep. 2023
During a search of the Chevy, police found a plastic bag with an unknown white powder.
—John Benson, cleveland, 8 Sep. 2023
The Indianapolis Star, 6 Sep. 2023
With a new coaching staff this season and a plenty of players new to the program, Louisville needed a game to work out its unknowns.
—Alexis Cubit, The Courier-Journal, 4 Sep. 2023
Looking ahead: Developers have expressed a reluctance to invest in the area due to the many environmental unknowns — including in Texas, where offshore wind could be especially lucrative as the state looks to increase capacity to help alleviate strain on its power grid.
—Breanne Deppisch, Washington Examiner, 28 Aug. 2023
That’s to a whole bunch of unknown, unknowns with the legal calendar.
—Nbc Universal, NBC News, 27 Aug. 2023
And then beyond the funding, there is a huge unknown around staffing.
—Emily Goodykoontz, Anchorage Daily News, 23 Aug. 2023
There are still many unknowns as the Cougars prepare to open the season.
—Kevin Reynolds, The Salt Lake Tribune, 29 Aug. 2023
There are still many unknowns about the long-term consequences of inhaling wildfire particles, Henderson says, in part because sustained exposure is a relatively new phenomenon.
—Omar Mouallem, WIRED, 23 Aug. 2023
His remains were declared unrecoverable and were interred at the National Memorial Cemetery of the Pacific in Honolulu, Hawaii with other unknowns from the Korean War.
—Aurora Sousanis, Detroit Free Press, 18 Aug. 2023
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Adjective
The effect these words will have on President Putin is unknown.
—Dan Brooks, New York Times, 12 Sep. 2023
Its full impact on reservation systems and casino floors in Las Vegas, the company's base, as well as at properties in Maryland, Massachusetts, Michigan, Mississippi, New Jersey, New York and Ohio, was unknown, spokesperson Brian Ahern said.
—Dennis Romero, NBC News, 12 Sep. 2023
The exact number is unknown, but firefighter union leaders say 341 FDNY members have died of illnesses related to 9/11, CBS New York reports.
—CBS News, 11 Sep. 2023
The extent of the injuries was unknown, Deputy Fire Chief Dan Kline told CNN in a phone call.
—Michelle Watson, CNN, 11 Sep. 2023
Amtrak’s exact return date to the Gulf Coast remains unknown, but the Mobile City Council will play a major role in determining the extent of the Port City’s involvement.
—John Sharp | Jsharp@al.com, al, 9 Sep. 2023
The exact cause is unknown, but psoriasis is believed to be related to an immune system malfunction that causes skin cells to grow too quickly, leading to the formation of the scaly patches, and may be triggered by stress, infections, or certain medications, explains Dr. Kamangar.
—Andi Breitowich, Women's Health, 8 Sep. 2023
Those sales also release an unknown amount of weaponry into the world.
—Nick Penzenstadler, USA TODAY, 8 Sep. 2023
During a search of the Chevy, police found a plastic bag with an unknown white powder.
—John Benson, cleveland, 8 Sep. 2023
Noun
The rookie quarterback is going to face a lot of unknowns of his own in the season opener — looks Jacksonville has designed to make Richardson’s life miserable — but the Jaguars do not have a database yet of the plays and formations that give the Colts rookie trouble.
—The Indianapolis Star, 6 Sep. 2023
With a new coaching staff this season and a plenty of players new to the program, Louisville needed a game to work out its unknowns.
—Alexis Cubit, The Courier-Journal, 4 Sep. 2023
Looking ahead: Developers have expressed a reluctance to invest in the area due to the many environmental unknowns — including in Texas, where offshore wind could be especially lucrative as the state looks to increase capacity to help alleviate strain on its power grid.
—Breanne Deppisch, Washington Examiner, 28 Aug. 2023
That’s to a whole bunch of unknown, unknowns with the legal calendar.
—Nbc Universal, NBC News, 27 Aug. 2023
And then beyond the funding, there is a huge unknown around staffing.
—Emily Goodykoontz, Anchorage Daily News, 23 Aug. 2023
There are still many unknowns as the Cougars prepare to open the season.
—Kevin Reynolds, The Salt Lake Tribune, 29 Aug. 2023
There are still many unknowns about the long-term consequences of inhaling wildfire particles, Henderson says, in part because sustained exposure is a relatively new phenomenon.
—Omar Mouallem, WIRED, 23 Aug. 2023
His remains were declared unrecoverable and were interred at the National Memorial Cemetery of the Pacific in Honolulu, Hawaii with other unknowns from the Korean War.
—Aurora Sousanis, Detroit Free Press, 18 Aug. 2023
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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
Phrases Containing unknown
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Dictionary Entries Near unknown
Cite this Entry
“Unknown.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unknown. Accessed 23 Sep. 2023.
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Kids Definition
unknown
1 of 2 adjective
un·known
ˌən-ˈnōn 
: not known
also
: having an unknown value
an unknown quantity
unknown
2 of 2 noun1
: 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
Nglish: Translation of unknown for Spanish Speakers
Britannica English: Translation of unknown for Arabic Speakers
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