Source : Webster's Revised Unabridged Dictionary (1913)

Grogram \Grog"ram\, Grogran \Grog"ran\, n. [OF. gros-grain,
   lit., gros-grain, of a coarse texture. See {Gross}, and
   {Grain} a kernel, and cf. {Grog}.]
   A coarse stuff made of silk and mohair, or of coarse silk.

Source : WordNet®

grogram
     n : a coarse fabric of silk mixed with wool or mohair and often
         stiffened with gum