rat

[rat]

noun

1. any of several long-tailed rodents of the family Muridae, of the genus Rattus and related genera, distinguished from the mouse by being larger.

2. any of various mammals similar to or related to the long-tailed rodents of the genus Rattus.

3. Slang.,  a scoundrel.

4. Slang.

   1. a person who abandons or betrays their party or associates, especially in a time of trouble.

   2. an informer.

   3. a scab laborer.

5. Slang.,  a person who frequents a specified place: gym rats.

   a mall rat;

   gym rats.

6. a pad with tapered ends formerly used in women's hairstyles to give the appearance of greater thickness.

interjection

1. Slang.,  rats, (an exclamation of disappointment, disgust, or disbelief.)

verb (used without object)

ratted, ratting 

1. Slang.

   1. to desert one's party or associates, especially in a time of trouble.

   2. to turn informer; squeal.

      He ratted on the gang, and the police arrested them.

   3. to work as a scab.

2. to hunt or catch rats.

verb (used with object)

ratted, ratting 

1. to make (the hair) appear thicker by use of a small pad of material or by teasing.

verb phrase

1. rat out,  to inform on.

   He ratted out his partners in exchange for a lighter sentence.

rat

/ ræt /

noun

1. any of numerous long-tailed murine rodents, esp of the genus Rattus , that are similar to but larger than mice and are now distributed all over the world See also brown rat black rat

2. informal,  a person who deserts his or her friends or associates, esp in time of trouble

3. informal,  a worker who works during a strike; blackleg; scab

4. slang,  an informer; stool pigeon

5. informal,  a despicable person

6. to detect something suspicious

verb

1. informal

   1. to divulge secret information (about); betray the trust (of)

   2. to default (on); abandon

      he ratted on the project at the last minute

2. to hunt and kill rats

Other Word Forms

• ratlike adjective

Word History and Origins

Origin of rat¹

First recorded before 1000; Middle English rat(t)te, Old English ræt; cognate with Dutch rat, German Ratz, Ratte

Word History and Origins

Origin of rat¹

Old English rætt ; related to Old Saxon ratta , Old High German rato

Idioms and Phrases

Idioms

1. smell a rat, to suspect or surmise treachery; have suspicion.

   After noting several discrepancies in his client's story, the attorney began to smell a rat.

More idioms and phrases containing rat

• like a drowned rat
• smell a rat

Example Sentences

Yet the pressures - the ones that are pushing more Chinese youth to quit the rat race, "lie flat" and take their frustrations out online - remain.

From BBC

He put down peppermint oil and rat poison and so far they haven't returned.

From BBC

Still others got it by eating infected wild birds, rats or mice, or from contact with dairy workers’ contaminated clothes or boots.

From Los Angeles Times

Scientists have for the first time located the "mileage clock" inside a brain - by recording the brain activity of running rats.

From BBC

The rains have stranded millions mid-commute, left cars floating in streets that have turned into rivers and caused outbreaks of leptospirosis, a liver ailment that spreads through the excrement of sewer rats.

From BBC