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optical device having a triangular shape and made of glass or quartz; used to deviate a beam or invert an image

optical device having a triangular shape and made of glass or quartz; used to deviate a beam or invert an image

A solid whose bases or ends are any similar, equal, and parallel plane figures, and whose sides are parallelograms.

A transparent body, with usually three rectangular plane faces or sides, and two equal and parallel triangular ends or bases; -- used in experiments on refraction, dispersion, etc.

A solid whose hases are similar, equal, and parallel, and whose sides are parallelograms; such a solid, having triangular ends and made of glass or other transparent substance: used for separating the colors in the light ray.

Small triangular column of glass.

(geom.) A solid whose ends are similar, equal, and parallel planes, and whose sides are parallelograms: (optics) a solid glass, triangular shaped body.

A solid, the sides of which are parallelograms, and the ends similar, equal, and parallel planes.

A solid whose bases are similar equal and parallel plane figures, and whose faces are parallelograms; spectrum.

A solid with a triangular or polygonal cross-section.

A solid the sides of which are parallelograms and its cross section a figure of three or more sides.

n. [Latin, Greek] A solid whose bases or ends are any similar, equal, and parallel plane figures, and whose sides are parallelograms; -a transparent body with, usually, three rectangular plane faces or sides, and two equal and parallel triangular ends or bases.