The Collaborative International Dictionary of English v.0.48:

crumpet \crump"et\ (kr[u^]mp"[e^]t), n. [Prob. from W. crempog,
   crammwgth, a pancake or fritter.]
   1. A kind of large, thin, unsweetened muffin or cake, light
      and spongy, and cooked on a griddle or spider, or
      sometimes toasted.
      [1913 Webster]

   2. a sexually attractive woman. [British slang] --RHUD
      [PJC]

WordNet (r) 3.0 (2006):

crumpet
    n 1: a thick soft cake with a porous texture; cooked on a
         griddle

Moby Thesaurus II by Grady Ward, 1.0:

25 Moby Thesaurus words for "crumpet":
   Danish, Danish pastry, English muffin, Parker House roll,
   Yorkshire pudding, bagel, bialy, bialystoker, bun,
   clover-leaf roll, coffee cake, crescent roll, croissant, cross bun,
   gem, hard roll, hot cross bun, kaiser roll, muffin, onion roll,
   pinwheel roll, popover, roll, scone, soft roll