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A space left unroofed over the court of a Roman dwelling, through which the rain fell into the impluvium or cistern.

kom-pl[=oo]'vi-um, n. a quadrangular open space in the middle of a Roman house, which carried the rain-water from the roofs to a basin (impluvium) placed below. [L.]

[L.] A square open space in the middle of a Roman atrium (q.v.), towards which the roof sloped so that the rain fell into a tank below.