Definition of pyramid
(Entry 1 of 2)
1a : an ancient massive structure found especially in Egypt having typically a square ground plan, outside walls in the form of four triangles that meet in a point at the top, and inner sepulchral chambers
b : a structure or object of similar form
2 : a polyhedron having for its base a polygon and for faces triangles with a common vertex — see Volume Formulas Table
3 : a crystalline form each face of which intersects the vertical axis and either two lateral axes or in the tetragonal system one lateral axis
4 : an anatomical structure resembling a pyramid: such as
a : any of the conical masses that project from the renal medulla into the renal pelvis
b : either of two large bundles of motor fibers from the cerebral cortex that reach the medulla oblongata and are continuous with the pyramidal tracts of the spinal cord
5 : an immaterial structure built on a broad supporting base and narrowing gradually to an apex
the socioeconomic pyramid
pyramid
verbpyramided; pyramiding; pyramids
Definition of pyramid (Entry 2 of 2)
1 : to speculate (as on a security or commodity exchange) by using paper profits as margin for additional transactions
2 : to increase rapidly and progressively step by step on a broad base
1 : to arrange or build up as if on the base of a pyramid
2 : to use (something, such as profits) in speculative pyramiding
3 : to increase the impact of (something, such as a tax assessed at the production level) on the ultimate consumer by treating as a cost subject to markup
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Time Traveler for pyramid
The first known use of pyramid was in 1549
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