Definition for thermals (2 of 2)
Examples from the Web for thermals
I asked, watching buzzards, white-backed vultures, and tawny eagles corkscrew skyward on thermals.Walking With Wildebeests: Exploring the Serengeti on Foot|Joanna Eede|July 9, 2013|DAILY BEAST
British Dictionary definitions for thermals
Word Origin and History for thermals
1756, "having to do with hot springs," from French thermal (Buffon), from Greek therme "heat," from PIE *ghwerm-/*ghworm- "warm" (cf. Latin fornax "an oven, kiln," formus "warm," Old English wearm; see warm). Sense of "having to do with heat" is first recorded 1837. The noun meaning "rising current of relatively warm air" is recorded from 1933.