thermal

From Wiktionary

Pronunciation[change]

Adjective[change]

Positive
thermal

Comparative
none

Superlative
none

Thermal pools
  1. Thermal is about, or using, heat.
    He swam in the thermal pool.

Noun[change]

Singular
thermal

Plural
thermals

  1. A thermal is a rising mass of warm air.
    We could see the bird soaring in the thermal.