Pyramid /(?)/

Pyr·a·mid

Pyramid

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.
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. (Geom.)
The game of pool in which the balls are placed in the form of a triangle at spot. (Billiards) [Eng.]
a fraudulent investment scheme in which the manager promises high profits, but instead of investing the money in a genuine profit-making activity, uses the money from later investors to pay the profits to earlier investors; -- also called pyramid scheme or pyramid operation. This process inevitably collapses when insufficient new investors are available, leaving the later investors with total or near-total losses of their investments. The managers usually blame government regulations or interference for the collapse of the scheme, rather than admit fraud. (Finance)

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

v. i.

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. A similar process of reinvesting gains or winnings (as of a gamble), but not involving operation on margin, is called a parlay. (Speculation)

v. t.

To use, or to deal in, in a pyramiding transaction. See Pyramid, v. i. (Speculation)