Definition of thermal
(Entry 1 of 2)
1a
: of, relating to, or caused by heat
thermal stress thermal insulation
b
: being or involving a state of matter dependent upon temperature
thermal conductivity thermal agitation of molecular structure
c
: having low energies of the order of those due to thermal agitation
thermal neutrons
2
: designed (as with insulating air spaces) to prevent the dissipation of body heat
thermal underwear
3
[Latin thermae public baths, from Greek thermai, plural of thermē]
: of, relating to, or marked by the presence of hot springs
thermal waters
thermal
nounDefinition of thermal (Entry 2 of 2)
: a rising body of warm air
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Merriam-Webster unabridged
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Time Traveler for thermal
The first known use of thermal was in 1742
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