'Martian' definitions:

Definition of 'Martian'

(from WordNet)
adjective
Of or relating to the planet Mars (or its fictional inhabitants)
noun
Imaginary people who live on the planet Mars

Definition of 'Martian'

From: GCIDE
  • Martian \Mar"tian\, prop. a. [L. Martius.] Of or pertaining to Mars, the Roman god of war, or to the planet bearing his name; martial. [Webster 1913 Suppl.]

Definition of 'Martian'

From: GCIDE
  • Martian \Mar"tian\, prop. n. An inhabitant of the planet Mars; -- fictional or hypothetical. --Du Maurier. [Webster 1913 Suppl.]
  • Note: In science fiction, it has often been postulated that there are intelligent creatures living on Mars, but no strong evidence of any form of life on Mars has been observed up to the end of 1998.