Hyp"o*caust (?), n. [L. hypocaustum, Gr. ; under + to burn: cf. F. hypocauste.] Anc. Arch.
A furnace, esp. one connected with a series of small chambers and flues of tiles or other masonry through which the heat of a fire was distributed to rooms above. This contrivance, first used in bath, was afterwards adopted in private houses.
© Webster 1913.