- a person who abandons or betrays his or her party or associates, especially in a time of trouble.
- an informer.
- a scab laborer.
verb (used without object), rat·ted, rat·ting.
- to desert one's party or associates, especially in a time of trouble.
- to turn informer; squeal: He ratted on the gang, and the police arrested them.
- to work as a scab.
verb (used with object), rat·ted, rat·ting.
- rat cheese,
- rat claw foot,
- rat fink,
- rat guard,
- rat islands
Origin of rat
Examples from the Web for rat
One rat had once fallen on his head, he said, during a rat raid of a local home.
Since rat root comes from a plant that grows on the edge of the lake there are concerns that the plant is carrying toxins.
A cabin filled with the Rat Pack and the ladies who loved them.
Not that the Rat Pack party days were completely behind him.
A flea, Xenopsylla cheopis, from an infected little mammal—usually a rat—can hop from the dying rat onto a human and bite it.It’s Not Time to Worry About China’s Plague Just Yet|Kent Sepkowitz|July 23, 2014|DAILY BEAST
Giddings ran, the Rat River call echoing again down the hall behind him.Held for Orders|Frank H. Spearman
Me tink pilot smell a rat, for ebery time he hear a noise on deck he come out of his cabin and look round.By Sheer Pluck|G. A. Henty
Rat me, if I had not misgivings that it might prove to be so.Micah Clarke|Arthur Conan Doyle
A rat will push down his tail into the tall-shaped bottle of preserves, and lick it after he has pulled it out.
I sat in the boat stripped and shivering, for shipwreck seemed certain, and I did not wish to be drowned like a rat.An Australian in China|George Ernest Morrison
verb rats, ratting or ratted
- to divulge secret information (about); betray the trust (of)
- to default (on); abandonhe ratted on the project at the last minute
Word Origin for rat
late Old English ræt "rat," of uncertain origin. Similar words are found in Celtic (Gaelic radan), Romanic (Italian ratto, Spanish rata, French rat) and Germanic (Old Saxon ratta; Dutch rat; German Ratte, dialectal Ratz; Swedish råtta, Danish rotte) languages, but connection is uncertain and origin unknown. In all this it is very much like cat.
Perhaps from Vulgar Latin *rattus, but Weekley thinks this is of Germanic origin, "the animal having come from the East with the race-migrations" and the word passing thence to the Romanic languages. American Heritage and Tucker connect Old English ræt to Latin rodere and thus PIE *red- "to scrape, scratch, gnaw," source of rodent (q.v.). Klein says there is no such connection and suggests a possible cognate in Greek rhine "file, rasp." Weekley connects them with a question mark and Barnhart writes, "the relationship to each other of the Germanic, Romance, and Celtic words for rat is uncertain." OED says "probable" the rat word spread from Germanic to Romanic, but takes no position on ultimate origin.
RATS. Of these there are the following kinds: a black rat and a grey rat, a py-rat and a cu-rat. ["Dictionary of the Vulgar Tongue," Grose, 1788]
Middle English common form was ratton, from augmented Old French form raton. Sense of "one who abandons his associates" (1620s) is from belief that rats leave a ship about to sink or a house about to fall and led to meaning "traitor, informant" (1902; verb 1910). Interjection rats is American English, 1886. To smell a rat is 1540s; "to be put on the watch by suspicion as the cat by the scent of a rat; to suspect danger" [Johnson]. _____-rat, "person who frequents _____" (in earliest reference dock-rat) is from 1864.
1812, "to desert one's party; 1864 as "to catch rats;" 1921 as "to peach on, inform on, behave dishonestly toward;" from rat (n.). Related: Ratted; ratting.
In addition to the idioms beginning with rat
- rat on
- rat race
- like a drowned rat
- smell a rat