| Idiom | Meaning | Example | 
| rap your knuckles | 
(See get your knuckles rapped)
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| rat fink | 
person who tattles, one who squeals, fink
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You rat fink! Did you blab  to Mom and Dad? Did you tell them?   
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| rat on | 
tell the police or the authorities, squeal, tell on
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Billy won't rat on me. He won't tell the teacher.
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| rat race | 
fast pace, busy schedule, living/working in the city
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What a rat race! I want to leave the city and live in the country.
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| ratch | 
damage, wreck, trash
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Who ratched the gears on my bike? I can't shift into low!
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| rats | 
oh no, darn, nuts
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Rats! We have a flat tire!
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| rattle my chain | 
annoy me, anger me, get under my skin
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That woman rattles my chain, the way she gossips about me!
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| rattle on | 
continue to talk, ramble, hold forth
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The professor was rattling on about Canadian culture.
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| rattle sabres | 
threaten to attack, appear to be preparing for war
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The workers are rattling their sabres, but they won't strike.
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| raw deal | 
(See a raw deal)
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