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[priz-moid] /ˈprɪz mɔɪd/
noun, Geometry
a solid having sides that are trapezoids and bases or ends that are parallel and similar but not congruent polygons.
Compare prism (def 2).
Origin of prismoid
1695-1705; prism + -oid
Related forms
prismoidal, adjective Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for prismoid
  • The body is strong, and of well-marked prismoid form.
  • It is conveniently described in two portions, viz, a medial flattened part and a narrow lateral prismoid portion.
British Dictionary definitions for prismoid


a prismatoid having an equal number of vertices in each of the two parallel planes and whose sides are trapeziums or parallelograms
Derived Forms
prismoidal, adjective
Word Origin
C18: from French prismoïde; see prism, -oid
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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