Private information, secret warning. In horse-racing, it means such secret information as may guide the person tipped to make bets advantageously. A “straight tip” comes straight or direct from the owner or trainer of the horse in question. A man will sometimes give the police the “tip,” or hint where a gang of confederates lie concealed, or where law-breakers may be found. Thus, houses of ill-fame and keepers of clandestine gaming houses in league with the police, receive the “tip” when spies are on them or legal danger is abroad.
“If he told the police, he felt assured that the `tip' would be given to the parties concerned, and his efforts would be frustrated.” —Mr, Stead's defence, November 2nd, 1885.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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