Definition of unknown
(Entry 1 of 2)
: not known or not well-known also : having an unknown value an unknown quantity
unknown
nounDefinition 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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Time Traveler for unknown
The first known use of unknown was in the 14th century
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