WordWeb Online

1. Relating to or associated with heat
   "thermal movements of molecules";
   - thermic, caloric
    
2. Caused by or designed to retain heat
   "a thermal burn"; "thermal underwear"
    
3. Of or relating to a hot spring
   "thermal water"

1. Rising current of warm air

Derived forms: thermals

See also: hot

Type of: air current, current of air, wind

Encyclopedia: Thermal, California