The Collaborative International Dictionary of English v.0.48:

Chervil \Cher"vil\, n. [AS. cerfille, fr. L. caerefolium,
   chaerephyllum, Gr. ?; ? to rejoice + ? leaf.] (Bot.)
   A plant (Anthriscus cerefolium) with pinnately divided
   aromatic leaves, of which several curled varieties are used
   in soups and salads.
   [1913 Webster]

WordNet (r) 3.0 (2006):

chervil
    n 1: aromatic annual Old World herb cultivated for its finely
         divided and often curly leaves for use especially in soups
         and salads [syn: chervil, beaked parsley, Anthriscus
         cereifolium]
    2: fresh ferny parsley-like leaves used as a garnish with
       chicken and veal and omelets and green salads and spinach