pyramid

n. a polyhedron having a polygonal base and triangular sides with a common vertex n. (stock market) a series of transactions in which the speculator increases his holdings by using the rising market value of those holdings as margin for further purchases n. a massive monument with a square base and four triangular sides; begun by Cheops around 2700 BC as royal tombs in ancient Egypt v. enlarge one's holdings on an exchange on a continued rise by using paper profits as margin to buy additional amounts