Therm
/θɜːrm/noun
A unit of heat equal to 100,000 British thermal units, used especially to measure natural-gas consumption.
Did you know?The same ancient root behind therm also produced Greek thermos and is related to English warm, linking modern energy billing to one of humanity’s oldest words for heat.
Etymological Timeline
Proto-Indo-European
PIE
*gʷher-
“To heat or warm”
Ancient Greek
Greek
θερμός (thermos)
“Hot or warm”
Ancient Greek
Greek
θέρμη (thermē)
“Heat”
19th Century
English
therm
“A coined unit for measuring heat”
Modern English
English
therm
“A unit equal to 100,000 British thermal units, especially used for natural gas”