The Collaborative International Dictionary of English v.0.48:

Patty \Pat"ty\, n.; pl. Patties. [F. p[^a]t['e]. See Pasty.]
   A little pie.
   [1913 Webster]

WordNet (r) 3.0 (2006):

patty
    n 1: small flat mass of chopped food [syn: patty, cake]
    2: small pie or pasty
    3: round flat candy