D defs.my
Entry 1 sense Webster, 1913

Isothermal

/īsˌ-əth-ẽrm'-əl/ · I·so·ther·mal · IPA /ˌaɪsəθˈɜrməl/
01 a. Relating to equality of temperature, or an isotherm.
  1. 1.
    Relating to equality of temperature, or an isotherm.(Phys. Geog.)
Phrases & compounds
Isothermal line — An isotherm
Isothermal zones — spaces on opposite sides of the equator having the same mean temperature, and bounded by corresponding isothermal lines.