The Collaborative International Dictionary of English v.0.48:

Bombazine \Bom`ba*zine"\, n. [F. bombasin, LL. bombacinium,
   bambacinium, L. bombycinus silken, bombycinum a silk or
   cotton texture, fr. bombyx silk, silkworm, Gr. ?. Cf.
   Bombast, Bombycinous.]
   A twilled fabric for dresses, of which the warp is silk, and
   the weft worsted. Black bombazine has been much used for
   mourning garments. [Sometimes spelt bombasin, and
   bombasine.] --Tomlinson.
   [1913 Webster]