1. Not known
   "an unknown writer"; "an unknown source"; "an unknown amount"; "an unknown island"
    
2. Not known before
   "don't let anyone unknown into the house";
   - strange
    
3. Not known to exist
   "things obscurely felt surged up from unknown depths"
    
4. Not famous or acclaimed
   "an unknown family";
   - obscure, unsung
    
5. Having a source that is not known or whose name is unknown
   "a poem by an unknown author";
   - nameless, unidentified, unnamed

1. A variable whose values are solutions of an equation
   "They worked to solve for the unknown in the complex equation";
   - unknown quantity
    
2. Anyone who does not belong in the environment in which they are found
   "The small town residents regarded the newcomer as an unknown";
   - stranger, alien
    
3. An unknown and unexplored region
   "they came like angels out of the unknown";
   - unknown region, terra incognita

Derived forms: unknowns

See also: anon., anonymous, chartless, inglorious, little-known, unacknowledged, unbeknown, unbeknownst, uncharted, undiagnosed, undiscovered, unexplored, unfamiliar, unheard-of, unidentified, unmapped, unsuspected

Type of: interloper, intruder, region, trespasser, variable

Antonym: known

Encyclopedia: Unknown