from
The Collaborative International Dictionary of English v.0.48
Pyramid \Pyr"a*mid\, n. [L. pyramis, -idis, fr. Gr. ?, ?, of
Egyptian origin: cf. F. pyramide.]
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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.
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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.
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3. pl. (Billiards) The game of pool in which the balls are
placed in the form of a triangle at spot. [Eng.]
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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.
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