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

Ghost’s exact age is unknown, but based on her weight and size “we can approximate she is in that age range,” the aquarium said.

From Los Angeles Times

Port officials have described the incident as an accident, though Crecy said the investigation was early and “still a dynamic situation with many unknowns.”

From Los Angeles Times

“Color Theories” reaches its apex when Torres begins discussing the space between the shades black and white — neither representing good nor evil, but rather the known and the unknown.

From Los Angeles Times

"With the safety of citizens in mind, we urge that in the event of observing an unknown object or its debris, do not approach, touch, or move it," the military wrote on X.

From BBC

The motive for the attack, which resembles the shocking killing of a lawmaker earlier this year, is unknown.

From BBC

Related Words

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