'Ratter' definitions:

Definition of 'ratter'

From: WordNet
noun
A disloyal person who betrays or deserts his cause or religion or political party or friend etc. [syn: deserter, apostate, renegade, turncoat, recreant, ratter]
noun
Any of several breeds of terrier developed to catch rats [syn: rat terrier, ratter]

Definition of 'Ratter'

From: GCIDE
  • Ratter \Rat"ter\ (r[a^]t"t[~e]r), n.
  • 1. One who, or that which, rats, as one who deserts his party. [1913 Webster]
  • 2. Anything which catches rats; esp., a dog trained to catch rats; a rat terrier. See Terrier. [1913 Webster]