prismatoid

WordNet 3.6
 n prismatoid a polyhedron whose vertices all lie in one or the other of two parallel planes; the faces that lie in those planes are the bases of the prismatoid
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Century Dictionary and Cyclopedia

 n prismatoid A solid having two parallel polygonal bases connected by triangular faces. If A and C are the areas of the bases of a prismatoid, and B that of the section halfway between them, then, h being the altitude, August's formula for the solid contents is ⅙ h (A + 4B + C).
 n prismatoid A term used by N. Story Maskelyne for a crystal form whose faces are parallel to one of the crystallographic axes while meeting the other two axes.
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Chambers's Twentieth Century Dictionary

 ns Prismatoid a figure in the form of a prism
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Chambers's Twentieth Century Dictionary
L.,—Gr. prisma, atos.
In science:
The second possibility is to use prismatoidal coordinates [LS01].
A new construction of perfectly matched layers for the linearized Euler equations
The geometry of the computational domain is discretized with simple geometrical patches, JCMsuite uses tetrahedral or prismatoidal (3D) patches.
Benchmark of Rigorous Methods for Electromagnetic Field Simulations
The use of prismatoidal patches is an advantage for layered geometries, as in photomask simulations.
Benchmark of Rigorous Methods for Electromagnetic Field Simulations
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