n. a variable whose values are solutions of an equation

n. an unknown and unexplored region; "they came like angels out the unknown"

adj. being or having an unknown or unnamed source; "a poem by an unknown author"; "corporations responsible to nameless owners"; "an unnamed donor"

adj. not known before; "used many strange words"; "saw many strange faces in the crowd"; "don't let anyone unknown into the house"

adj. not famous or acclaimed; "an obscure family"; "unsung heroes of the war"

adj. not known; "an unknown amount"; "an unknown island"; "an unknown writer"; "an unknown source"

adj. not known to exist; "things obscurely felt surged up from unknown depths"