Bipyramidal :: Bipyramidal (a.) Consisting of two pyramids placed base to base; having a pyramid at each of the extremities of a prism, as in quartz crystals..
Pyramid :: Pyramid (n.) A solid body standing on a triangular, square, or polygonal base, and terminating in a point at the top; especially, a structure or edifice of this shape..
Pyramid :: Pyramid (n.) A solid figure contained by a plane rectilineal figure as base and several triangles which have a common vertex and whose bases are sides of the base.
Pyramid :: Pyramid (n.) The game of pool in which the balls are placed in the form of a triangle at spot.
Pyramidal :: Pyramidal (a.) Of or pertaining to a pyramid; in the form of a a pyramid; pyramidical; as, pyramidal cleavage..