variants or thermo-
1
: heat
thermostat
2
: thermoelectric
thermopile

Word History

Etymology

Greek, from thermē

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Cite this Entry

“Therm-.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/therm-. Accessed 9 Jun. 2026.

Medical Definition

therm

noun
: any of several units of quantity of heat: as
a
: 1000 kilogram calories
b
: 100,000 British thermal units
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