D defs.my
Entry 2 senses Webster, 1913

Ratter

/(răt"tẽr)/ · Rat·ter · IPA
01 n. One who, or that which, rats, as one who deserts his party.
  1. 1.
    One who, or that which, rats, as one who deserts his party.
  2. 2.
    Anything which catches rats; esp., a dog trained to catch rats; a rat terrier. See Terrier. See: Terrier