prism has definitions from the fields of physics,optics,mathematics,geometry
1
[ noun ] (mathematics,geometry) a polyhedron with two congruent and parallel faces (the bases) and whose lateral faces are parallelograms
2
[ noun ] (physics,optics) optical device having a triangular shape and made of glass or quartz; used to deviate a beam or invert an image

Synonyms

optical_prism

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