n. [ L. calefactio: cf. F. caléfaction. ]
n. [ Cf. F. raréfaction. See Rarefy. ] The act or process of rarefying; the state of being rarefied; -- opposed to condensation;
n. [ Cf. F. raréfaction. See Rarefy. ] The act or process of rarefying; the state of being rarefied; -- opposed to condensation;