Source : Webster's Revised Unabridged Dictionary (1913)

Monotype \Mon"o*type\, Monotypic \Mon`o*typ"ic\, a. [Mono- +
   -type: cf. F. monotype.] (Biol.)
   Having but one type; containing but one representative; as, a
   monotypic genus, which contains but one species.

Source : WordNet®

monotypic
     adj : consisting of only one type