Definition of heat index in English:

heat index

Syllabification: heat in·dex

noun

A quantity expressing the discomfort felt as a result of the combined effects of the temperature and humidity of the air.
More example sentences
  • If the air warmed to 95 degrees and the dew point stayed at 71, the relative humidity would be 44% and the heat index would be 101 degrees.
  • The first thing I do is fetch ice ($8 for a regular-size bag), a job that is hugely important because the heat index, with the humidity and asphalt, is roughly 174 degrees.
  • It will also read temperature, humidity, dew-point, wet bulb temperature, wind chill index, heat index, barometric pressure and altitude.

Get more from Oxford Dictionaries

Subscribe to remove adverts and access premium resources

Word of the day demoralize
Pronunciation: dɪˈmɒrəlʌɪz
verb
cause (someone) to lose confidence or hope