- Axis of a pyramid
- Pyramid Pyr"a*mid, n. [L. pyramis, -idis, fr. Gr. ?, ?, of
Egyptian origin: cf. F. pyramide.]
[1913 Webster]
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.
[1913 Webster]
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. [1913 Webster]
3. pl. (Billiards) The game of pool in which the balls are placed in the form of a triangle at spot. [Eng.] [1913 Webster]
4. (Finance) 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. [PJC]
{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. [1913 Webster]
The Collaborative International Dictionary of English. 2000.