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1

pyramid

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noun pyr·a·mid \ˈpir-ə-ˌmid\

Simple Definition of pyramid

  • : a very large structure built especially in ancient Egypt that has a square base and four triangular sides which form a point at the top

  • : a shape, object, or pile that is wide near the bottom and narrows gradually as it reaches the top

  • : something that resembles a pyramid in the way its parts are arranged or organized

Full Definition of pyramid

  1. 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. 2 :  a polyhedron having for its base a polygon and for faces triangles with a common vertex — see volume table

  3. 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. 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. 5 :  an immaterial structure built on a broad supporting base and narrowing gradually to an apex <the socioeconomic pyramid>

py·ra·mi·dal play \pə-ˈra-mə-dəl, ˌpir-ə-ˈmi-\ adjective
py·ra·mi·dal·ly adverb
pyr·a·mid·i·cal play \ˌpir-ə-ˈmi-di-kəl\ adjective

Examples of pyramid

  1. the ancient pyramids of Egypt



Illustration of pyramid

Origin of pyramid

Latin pyramid-, pyramis, from Greek


First Known Use: 1549


2

pyramid

verb pyr·a·mid

Definition of pyramid

  1. intransitive verb
  2. 1 :  to speculate (as on a security or commodity exchange) by using paper profits as margin for additional transactions

  3. 2 :  to increase rapidly and progressively step by step on a broad base

  4. transitive verb
  5. 1 :  to arrange or build up as if on the base of a pyramid

  6. 2 :  to use (as profits) in speculative pyramiding

  7. 3 :  to increase the impact of (as a tax assessed at the production level) on the ultimate consumer by treating as a cost subject to markup



Circa 1900

First Known Use of pyramid

circa 1900


Medical Dictionary

pyramid

play
noun pyr·a·mid \ˈpir-ə-ˌmid\

Medical Definition of pyramid

  1. 1:  a polyhedron having for its base a polygon and for faces triangles with a common vertex

  2. 2:  an anatomical structure resembling a pyramid: asa:  renal pyramidb:  either of two large bundles of motor fibers from the cerebral cortex that reach the medulla oblongata and are continuous with the corticospinal tracts of the spinal cordc:  a conical projection making up the central part of the inferior vermis of the cerebellum





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