Prism
WordNet
noun
(1) Optical device having a triangular shape and made of glass or quartz; used to deviate a beam or invert an image
(2) A polyhedron with two congruent and parallel faces (the bases) and whose lateral faces are parallelograms
WiktionaryText
Etymology
prisma, from πρίσμα prisma "something sawed", from πρίζειν prizein "to saw".
Noun
- A polyhedron with parallel ends of the same size and shape, the other faces being parallelogram-shaped sides.
- A transparent block in the shape of a prism (typically with triangular ends), used to split or reflect light.
- A crystal in which the faces are parallel to the vertical axis.