thermal Definition

thermal
adj

1. Belonging or relating to, caused by, or producing heat.

Thesaurus: warm, tepid, hot.
2. Said of clothing: designed to prevent the loss of heat from the body.

Example: thermal vest

noun

1. A rising current of warm air, used by birds, gliders and hang-gliders to move upwards.
2. Thermal clothing, especially underwear.

Form: thermals

Derivative: thermally
adverb

Etymology: 18c: from Greek therme heat.