1a rodent that resembles a large mouse, typically having a pointed snout and a long tail. Some kinds have become cosmopolitan and are sometimes responsible for transmitting diseases.
Family Muridae: many genera, including Rattus (the Old World rats), and several hundred species
Family Muridae: many genera, including Rattus (the Old World rats), and several hundred species
2 informal a despicable person, especially a man who has been deceitful or disloyal:her rat of a husband cheated on her
an informer:he became the most famous rat in mob history
3 [with modifier]North American informal a person who is associated with or frequents a specified place:LA mall rats
4US a pad used to give shape and fullness to a woman’s hair.
ზმნა
Universal
1 (usually as noun ratting) hunt or kill rats:ratting is second nature to a Jack Russell
2 informal desert one’s party, side, or cause:many of the clans rallied to his support, others ratted and joined the King’s forces
3 [with object]US shape (hair) with a rat.
rat on
(also North Americanrat someone out) informal inform on (someone):he refused to rat on his buddies
break (an agreement or promise):he accused the government of ratting on an earlier pledge
