Liq`ue*fac"tion (?), n. [L. liquefactio: cf. F. liqu'efaction. See Liquefy.]
The act or operation of making or becoming liquid; especially, the conversion of a solid into a liquid by the sole agency of heat.
The state of being liquid.
3. Chem. Physics
The act, process, or method, of reducing a gas or vapor to a liquid by cold or pressure; as, the liquefaction of oxygen or hydrogen.
© Webster 1913.