rat
1rat
noun \ˈrat\Definition of RAT
1
a : any of numerous rodents (Rattus and related genera) differing from the related mice especially by considerably larger size b : any of various similar rodents
2
3
: a pad over which a woman's hair is arranged
4
: a person who spends much time in a specified place <a mall rat>
— rat·like \-ˌlīk\ adjective
Examples of RAT
- a dirty old building infested by rats and mice
- I can't believe that rat turned us in to the police!
- No one understands why she's with a rat like him.
- Every night he goes to work out with the other gym rats.
Origin of RAT
Middle English, from Old English ræt; akin to Old High German ratta rat and perhaps to Latin rodere to gnaw — more at rodent
First Known Use: before 12th century
Related to RAT
- Synonyms
- betrayer, canary [slang], deep throat, fink, informant, nark [British], informer, rat fink, snitch, snitcher, squealer, stoolie, stool pigeon, talebearer, tattler, tattletale, telltale, whistle-blower
2rat
verbrat·tedrat·ting
Definition of RAT
intransitive verb
1
: to betray, desert, or inform on one's associates —usually used with on
2
: to catch or hunt rats
3
: to work as a scab
transitive verb
1
: to give (hair) the effect of greater quantity (as by use of a rat)
2
: to inform on : turn in —usually used with out <ratted out his accomplice>
Examples of RAT
- The teacher knows what we did, which means that somebody ratted.
First Known Use of RAT
1812
rat
noun \ˈrat\ (Medical Dictionary)Medical Definition of RAT
: any of the numerous rodents (family Muridae) of Rattus and related genera that differ from the murid mice by their usually considerably larger size and by features of the teeth and other structures and that include forms (as the brown rat, the black rat, and the roof rat) which live in and about human habitations and in ships, have become naturalized by commerce in most parts of the world, and are destructive pests consuming or destroying vast quantities of food and other goods and acting as vectors of various diseases (as bubonic plague)
rat
noun (Concise Encyclopedia)Any of more than 500 forms of Asian rodent (genus Rattus, family Muridae) that have been introduced worldwide. The black rat (Rattus rattus) and the Norway rat (R. norvegicus) are the aggressive, omnivorous animals commonly associated with the name. They prefer areas of human habitation, where they can easily find food. They have keen senses and can climb, jump, burrow, or gnaw their way into seemingly inaccessible places. They reproduce extremely rapidly (up to 150 offspring a year) and have few natural predators. Rats transmit numerous human diseases and have often destroyed grain supplies. The black rat is about 8 in. (20 cm) long, excluding the slightly longer tail. The Norway rat (also called the brown, barn, sewer, or wharf rat) has proportionately smaller ears and a shorter tail. Laboratory rats are strains of the Norway rat. The name rat is applied, without scientific basis, to other rodents (e.g., kangaroo rat, wood rat).
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