The definition of a rat is a rodent with a lengthy tail, or is slang for a sneaky person.(noun)
Rat is defined as to tease hair, or to hunt for rats, or is slang for betray.(verb)
See rat in Webster's New World College Dictionary
Origin: ME ratte < OE ræt, akin to Ger ratz, ratte < PGmc *ratto < ? IE base *red-, *rōd-, to scratch, gnaw > L radere, to scrape, rodere, to gnaw
See rat in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old English rǽt; see rēd- in Indo-European roots.
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