Pyr"a*mid (?), n. [L. pyramis, -idis, fr. Gr. &?;, &?;, of Egyptian origin: cf. F. pyramide backlinks.]

1. 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.

2. (Geom.) 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.

3. pl. (Billiards) The game of pool in which the balls are placed in the form of a triangle at spot. [Eng.]

Altitude of a pyramid (Geom.), the perpendicular distance from the vertex to the plane of the base. --
Axis of a pyramid (Geom.), a straight line drawn from the vertex to the center of the base. --
Earth pyramid. (Geol.) See Earth pillars, under Earth. --
Right pyramid (Geom.) a pyramid whose axis is perpendicular to the base.

© Webster 1913

Pyr"a*mid (?), v. i. (Speculation) To enlarge one's holding or interest in a series of operations on a continued rise or decline by using the profits to buy or sell additional amounts on a margin, as where one buys on a 10% margin 100 shares of stock quoted at 100, holds it till it rises to 105, and then uses the paper profit to buy 50 shares more, etc. The series of operations constitutes a pyramid.

© Webster 1913

Pyr"a*mid, v. t. (Speculation) To use, or to deal in, in a pyramiding transaction. See Pyramid, v. i.

© Webster 1913

Pyr"a*mid, n. (Speculation) The series of operations involved in pyramiding. See Pyramid, v. i.

© Webster 1913