ADIABATIC

Ad′i‐a‐bat″ic (�), a. [[Gr. � not passable; ἀ priv. + � through + � to go.]] (Physics) Not giving out or receiving heat. — Ad′i‐a‐bat′ic‐al‐ly, adv. Adiabatic line or curve, a curve exhibiting the variations of pressure and volume of a fluid when it expands without either receiving or giving out heat. Rankine.