n.
Pronunciation: ' pir- ə - ˌ mid
Function: noun
Etymology: Latin pyramid-, pyramis, from Greek
Date: 1549
1 a : 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 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: as a : any of the conical masses that project from the renal medulla into the kidney 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 >
– py · ra · mi · dal \ p ə - ' ra-m ə -d ə l, ˌ pir- ə - ' mi- \ adjective
– py · ra · mi · dal · ly adverb
– pyr · a · mid · i · cal \ ˌ pir- ə - ' mi-di-k ə l \ adjective
pyramid[1]