Wordnet 3.0
NOUN (1)
1.
a chewer who makes a munching noise;
The Collaborative International Dictionary of English v.0.48:
Muncher \Munch"er\, n.
One who munches.
[1913 Webster]
WordNet (r) 3.0 (2006):
muncher
n 1: a chewer who makes a munching noise