A solid geometric figure whose two ends are similar, equal, and parallel rectilinear figures, and whose sides are parallelograms
A series of prisms used with a spectroscope to give increased dispersion of light.
A device for producing plane-polarized light, consisting of two pieces of optically clear calcite or Iceland spar cemented together with Canada balsam in the shape of a prism
A reflecting prism in which the light is reflected on two 45° surfaces and returned parallel to the incoming beam
A reflecting prism in which the reflecting surface is in two parts that are angled like the two sides of a pitched roof
(In singular and plural) binoculars containing two pairs of triangular prisms, introduced so as to shorten the instrument and improve the stereoscopic effect.
A prism whose cross-section is a right triangle, used for deflecting rays through 90 degrees (if they enter through one of the faces forming the right angle) or 180 degrees (if they enter through the hypotenuse face).
A mass of sedimentary material scraped off a region of oceanic crust during subduction and piled up at the edge of a continental crustal plate
Designating a prim or affected facial expression or manner of speaking. In extended use: affected mannerisms, superficial accomplishments.
A pair of binoculars using two Porro prisms at right angles, resulting in a conventional instrument with objective lenses that are further apart than the eyepieces
A pair of binoculars using two roof prisms, resulting in an instrument with parallel sides and objective lenses that are the same distance apart as the eyepieces