'hairball' definitions:

Definition of 'hairball'

From: WordNet
noun
A compact mass of hair that forms in the alimentary canal (especially in the stomach of animals as a result of licking fur) [syn: hairball, hair ball, trichobezoar]

Definition of 'hairball'

From: GCIDE
  • hairball \hair"ball`\, hair ball \hair" ball`\(h[^a]r"b[e^]l`), n. a compact mass of hair that forms in the stomach of animals as a result of licking fur; as, the cat coughed up a hairball right on the new rug. [WordNet sense 1 + 2] [WordNet 1.5]