Cra″ter (kr?t?r), n. [L. crater, cratera, a mixing vessel, the mouth of a volcano, Gr. κρατήρ, fr. κεραννύναι to mix; cf. Skr. çrī to mix, çir to cook, çrā to cook. Cf. Grail, in Holy Grail.] 1. The basinlike opening or mouth of a volcano, through which the chief eruption comes; similarly, the mouth of a geyser, about which a cone of silica is often built up.
2. (Mil.) The pit left by the explosion of a mine.
3. (Astron.) A constellation of the southen hemisphere; — called also the Cup.