unknown

[uhn-nohn]

adjective

1. not known; not within the range of one's knowledge, experience, or understanding; strange; unfamiliar.

2. not discovered, explored, identified, or ascertained.

   the unknown parts of Antarctica.

3. not widely known; not famous; obscure.

   an unknown writer.

noun

1. a thing, influence, area, factor, or person that is unknown.

   the many unknowns in modern medicine; The director cast an unknown in the leading role.

2. Mathematics.,  a symbol representing an unknown quantity: in algebra, analysis, etc., frequently represented by a letter from the last part of the alphabet, as x, y, or z.

unknown

/ ʌnˈnəʊn /

adjective

1. not known, understood, or recognized

2. not established, identified, or discovered

   an unknown island

3. not famous; undistinguished

   some unknown artist

4. a person or thing whose action, effect, etc, is unknown or unpredictable

noun

1. an unknown person, quantity, or thing

2. maths a variable, or the quantity it represents, the value of which is to be discovered by solving an equation; a variable in a conditional equation

   3y = 4x + 5 is an equation in two unknowns

Other Word Forms

• unknownness noun

Word History and Origins

Origin of unknown¹

First recorded in 1250–1300, unknown is from the Middle English word unknow(e)n. See un- ¹, known

Example Sentences

His was shot multiple times, and the motive behind the attack is unknown.

Read more on Los Angeles Times

Although the work they are doing presents certain risks due to exposure to unknown toxic materials, they said that the threat of encounters with ICE causes greater panic.

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"Other thefts are likely unreported and remain unknown as attributing cyber thefts to North Korea is not an exact science."

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Being unknown means voters struggle to work out what she is about, but it also presents an opportunity to move beyond the last Tory government and appear new and fresh.

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The announcement by a relatively unknown startup was impressive for a number of reasons, not least because the company said it cost much less to train than leading AI models.

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Related Words

• anonymous 
• exotic 
• foreign 
• nameless 
• new 
• remote 
• strange 
• uncharted 
• undiscovered 
• unexplained 
• unexplored 
• unfamiliar 
• unidentified 
• unnamed 
• unrecognized