- 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 rats
And in a city with large slums and poor sanitation, rats can thrive easily, fleas and all, to spread the plague.
The researchers first isolated a set of cells known as neural stem cells (NSCs) from the brains of rats.Fish Oil, Turmeric, and Ginseng, Oh My! Are ‘Brain Foods’ B.S.?|Dr. Anand Veeravagu, MD|October 10, 2014|DAILY BEAST
“Did you want to know about rats,” he asked, finally, as we walk down the hill to drink tea in his living room.
The results: Even moderate MDMA doses in conditions that mimic hot, crowded, social settings could be lethal to rats.Why Molly Is Especially Deadly at Summer Music Festivals|Abby Haglage|June 7, 2014|DAILY BEAST
So, they randomly select a poor villager and strap a bucket of rats against his chest.
Like rats, mice appear to act in companies, either under leadership or by common consent.Natural History in Anecdote|Various
This species is found almost exclusively in salt marshes, where they skulk about like rats.Bird Guide|Chester A. Reed
He saw himself a stowaway hidden in a hold, alone with rats and ships' biscuits.The Prophet of Berkeley Square|Robert Hichens
The Rats had developed a device that could make a star temporarily unstable, and they were ready to use it on Sol.The Measure of a Man|Randall Garrett
A lovely way to spend Christmas shut in like rats in a trap!A Lover in Homespun|F. Clifford Smith
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
expressing incredulity, disappointment, etc., 1886, from rat (n.).
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