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Synonyms

heat wave

American  
[heet weyv] / ˈhit ˌweɪv /
Or heatwave

noun

Meteorology, Climatology.
  1. a period of abnormally hot and usually humid weather; heat event.

    I moved to the coast up north because summer back home has become one long, unbearable heat wave.

  2. an air mass of high temperature covering an extended area and moving relatively slowly.

    Another heat wave is expected to form across the South and into the Northeast by week’s end.


heat wave British  

noun

  1. a continuous spell of abnormally hot weather

  2. (not in technical use) an extensive slow-moving air mass at a relatively high temperature

"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

Etymology

Origin of heat wave

First recorded in 1875–80

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

There has been no trend in the EPA heat wave index since 1895, except for the 1930s.

From The Wall Street Journal

Just weeks after major storms brought snow to the Sierra Nevada, a winter heat wave has all but eliminated California’s snowpack gains.

From Los Angeles Times

On Friday, the heat wave is poised to tie or even break several single-day temperature records in Los Angeles.

From Los Angeles Times

Some are even putting up their own mini weather stations to help them track hyperlocal trends to protect themselves from flooding and heat waves.

From The Wall Street Journal

Wait times have lengthened as power officials study whether there is enough power to support them while keeping the lights on for other customers, especially during heat waves and cold snaps when electricity demand surges.

From The Wall Street Journal