Definition of "rat" []

• Any of various long-tailed rodents resembling mice but larger, especially one of the genus Rattus. (noun)
• Any of various animals similar to one of these long-tailed rodents. (noun)
• Slang A despicable person, especially one who betrays or informs upon associates. (noun)
• Slang A scab laborer. (noun)
• A pad of material, typically hair, worn as part of a woman's coiffure to puff out her own hair. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "I felt in my soul that the rat -- yes, the _rat_, the RAT I had just seen, was that evil being in masquerade, and rambling through the house upon some infernal night lark."
• "Mariah was a rag-shaking terrier, who had only to hear the word rat to start digging."
• "Aiguy: Well, no – the physical determinist would say that the rat is always physically constrained, just like everything else, because there is no other way to be."