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warmer-upper

American  
[wawr-mer-uhp-er] / ˈwɔr mərˈʌp ər /

noun

Informal.
  1. something that provides one with invigorating warmth.

    Hot soup is a good warmer-upper after skiing.

  2. something that serves to warm up an audience or group of participants before a main event.

    Radio stations played martial music as a warmer-upper before the prime minister's speech.


Etymology

Origin of warmer-upper

1940–45; warm up + -er 1, applied pleonastically to both v. and particle