noun pen·ta·prism \ˈpentə+ˌ-\

Definition of pentaprism

  1. :  a pentagonal prism having one angle 90° and the others 112° 30′, producing a constant deviation of 90° for any wavelength, and used as a reflector in range finders

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Origin and Etymology of pentaprism

penta- + prism

Seen and Heard

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feeling or affected by lethargy

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