n. & v.
--n.
1. a any of several rodents of the genus Rattus (brown rat). b any similar rodent (muskrat; water-rat).
2 a deserter from a party, cause, difficult situation, etc.; a turncoat (from the superstition that rats desert a sinking ship).
3 colloq. an unpleasant person.
4 a worker who refuses to join a strike, or who blacklegs.
5 (in pl.) sl. an exclamation of contempt, annoyance, etc.
--v.intr. (ratted, ratting)
1. (of a person or dog) hunt or kill rats.
2 colloq. desert a cause, party, etc.
3 (foll. by on) a betray; let down. b inform on.
Phrases and idioms:
rat-catcher a person who rids buildings of rats etc. rat kangaroo Austral. any of various small ratlike marsupials of the family Potoroidae, having kangaroo-like hind limbs for jumping. rat race a fiercely competitive struggle for position, power, etc. rat's tail a thing shaped like a rat's tail, e.g. a tapering cylindrical file. rat-tail
1. the grenadier fish.
2 a horse with a hairless tail.
3 such a tail. rat-tail (or -tailed) spoon a spoon with a tail-like moulding from the handle to the back of the bowl.
Etymology: OE r{aelig}t & OF rat