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therm

1 American  
[thurm] / θɜrm /
Or therme

noun

Physics.
  1. any of several units of heat, as one equivalent to 1000 large calories or 100,000 British thermal units.


therm- 2 American  
  1. variant of thermo- before a vowel.

    thermesthesia.


-therm 3 American  
  1. variant of thermo- as final element in compound words.

    isotherm.


therm. 4 American  

abbreviation

  1. thermometer.


therm British  
/ θɜːm /

noun

  1. a unit of heat equal to 100 000 British thermal units. One therm is equal to 1.055 056 × 10 8 joules

"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 therm

First recorded in 1885–90, therm is from the Greek word thérmē heat