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Synonyms

tip-off

American  
[tip-awf, -of] / ˈtɪpˌɔf, -ˌɒf /

noun

Informal.
  1. the act of tipping off.

  2. a hint or warning.

    They got a tip-off on the raid.


tip-off British  

noun

  1. a warning or hint, esp given confidentially and based on inside information

  2. basketball the act or an instance of putting the ball in play by a jump ball

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

  1. (tr, adverb) to give a hint or warning to

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
tip off Idioms  
  1. Supply with secret or private information; also, warn or alert. For example, The broker often tipped her off about stocks about to go down in price, or Somehow they were tipped off and left the country before the police could catch them. [Colloquial; late 1800s]


Etymology

Origin of tip-off

First recorded in 1910–15; noun use of verb phrase tip off