thermal

Etymology

From French thermal, from New Latin *thermalis, from Ancient Greek θέρμη (thérmē, “heat”), from Proto-Indo-European *gʷʰer- (“to heat, warm”).

Pronunciation

• IPA^(key): /ˈθɝməl/

• Audio (Southern England):

  (file)

• Rhymes: -ɜː(ɹ)məl

Adjective

thermal (not comparable)

1. Pertaining to heat or temperature.
   • 2013 May-June, Charles T. Ambrose, “Alzheimer’s Disease”, in American Scientist, volume 101, number 3, page 200:

     Similar studies of rats have employed four different intracranial resorbable, slow sustained release systems—surgical foam, a thermal gel depot, a microcapsule or biodegradable polymer beads.

2. (fabric) Providing efficient insulation so as to keep the body warm.
3. Caused or brought about by heat.
4. (stone) Having a rough finish from treatment with a blowtorch.

Noun

thermal (plural thermals)

1. (meteorology) A column of rising air in the lower atmosphere created by uneven heating of a planet's surface.
   • 2019, Chigozie Obioma, An Orchestra of Minorities, Abacus (2019), page 91:

     The hawk had mounted its thermal by the time he got to the yard, flapping its wings violently against the updraft.

Verb

thermal (third-person singular simple present thermals, present participle thermaling or thermalling, simple past and past participle thermaled or thermalled)

1. (stone) To create a rough finish on stone by treating it with a high-temperature blowtorch.
2. (gliding, often in the present participle) To fly an unpowered aircraft in a thermal (column of rising air).

Further reading

• “thermal”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.
• “thermal”, in The Century Dictionary […], New York, N.Y.: The Century Co., 1911, →OCLC.

Etymology

From Ancient Greek.

Pronunciation

• IPA^(key): /tɛʁ.mal/

Adjective

thermal (feminine thermale, masculine plural thermaux, feminine plural thermales)

1. thermal

Further reading

• “thermal”, in Trésor de la langue française informatisé [Digitized Treasury of the French Language], 2012.

Adjective

thermal (not comparable)

1. thermal