The sport of setting a dog upon rats confined in a pit to see how many he will kill in a given time.(noun)
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Use "ratting" in a sentence
"After all, ratting is good fun, and difficult to come by in London."
"Political prisoner probably whose offence had been "ratting" -- and so his punishment was made "to fit the crime," as Mr. GILBERT's _Mikado_ used to observe."
"Godard once said that by "ratting" to the police she had emancipated herself."