The Collaborative International Dictionary of English v.0.48:

grassfinch \grass"finch`\ n.
   Any of several usually brightly-colored Australian
   weaverbirds; they are often kept as cage birds.

   Syn: grass finch.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

grassfinch
    n 1: usually brightly-colored Australian weaverbirds; often kept
         as cage birds [syn: grassfinch, grass finch]