The Collaborative International Dictionary of English v.0.48:

Dissyllabic \Dis`syl*lab"ic\ (d[i^]s`s[i^]l*l[a^]b"[i^]k), a.
   [Cf. F. dissyllabique. See Dissylable.]
   Consisting of two syllables only; as, a dissyllabic foot in
   poetry. --B. Jonson.
   [1913 Webster]