Mmmm, You Dirty Rat!

It’s the rare media mention of Wall Street con man Bernie Madoff that doesn’t contain the word “rat” in some context.

Bernard Madoff is an evil crook – but apparently not a rat.

The Big Rat’s off to the Big House for Life, What About the Little Rats?

Madoff may rat out co-conspirators

They [Mr. and Mrs. Madoff] seemed to stay apart from the herd,” the club member said. “They chose not to get into that social rat race.”

U.S. District Judge Denny Chin who presumably will sentence Madoff said that he’d sharply limit the number of Madoff victims who get to shake their fist in the swindler’s face and tell him what a rat he is…

It is almost inconceivable that Madoff could have spent 20 years squirreling away clients’ money in a Chase Manhattan bank account, conducting virtually no legitimate transactions, without anybody at Madoff Investment Securities smelling a rat –

The etymological origin of the word rat is lost in the mists of the long history shared by this repugnant animal and human beings. (I know, white rats make nice pets. I’m talking about nasty rats au naturel.)

The OED offers several possible origins, but concludes:

It is uncertain whether the Latin and Romance words are cognate with the Germanic words, or whether they were borrowed from Germanic, or vice versa; in any case the ultimate origin is uncertain; perhaps imitative of the sound of gnawing.

The OED also offers seven entries for rat as a noun and three for rat as a verb.

The literal meaning of rat is, of course, “a rodent resembling a large mouse, often with a naked or sparsely haired tail.”

Then there are the figurative uses that derive from the fact that rats are associated with filth and that they are said to be quick to leave a sinking ship or a falling house. The sense of rat as “one who abandons his associates” was in use in 1629.

rat as a noun
rat – a despicable person, especially one who betrays or informs upon associates.
rat – scab laborer
NOTE: a scab is either an employee who works while his colleagues are on strike, or an outsider hired to replace a striking worker.
rat – a pad of material, typically hair, worn as part of a woman’s coiffure to puff out her own hair.

rat as a verb
rat – intransitive verb – to desert a party, cause, or princple; to go over as a deserter; to abandon, desert, or betray any person or thing.
rat – transitive verb – to backcomb or tease hair
rat – intransitive – to act as an informer; to betray to the police or other authorities
rat on – to inform on a person
rat out – to inform on a person; to betray a person to the police or other authorities

Other rat words and expressions 
rat-fink – teenage slang from the 60s. A pleonasm since either rat or finkalone can mean an informant or, as verbs to inform.
rat-race - A fiercely competitive race or contest; spec. urban working life regarded as an unremitting struggle for wealth ., status, etc.
ratsbane – arsenic
rathole – messy, nasty place
rat-pack – juvenile gang; celebrities surrounding Frank Sinatra
to smell a rat – to suspect that something is wrong

Rat has even become a suffix to create words that mean “person who frequents” such and such a place: dock-rat, bar-rat, rug-rat, etc.

My brother, like many Cagney impersonators, thought he was quoting Cagney when he said, with appropriate grimaces and inflections, “Mmmmm, you dirty rat!” According to the Wikipedia Cagney bio, what Cagney really said in the movie Taxi! was

Come out and take it, you dirty, yellow-bellied rat, or I’ll give it to you through the door!”