prism

noun8

1. •
   A polyhedron with parallel ends of the same polygonal shape and size, the other faces being parallelogram-shaped sides.
2. •
   (figurative) A perspective that colours one's perception.

   • I had surveyed the landscape through the prism of poetry, which tinged every object with the hues of the rainbow. — 1820
3. •
   A transparent block in the shape of a prism, typically with triangular ends, used to reflect or refract light.
4. •
   A retroreflector (“device which reflects light back to its source with minimal scattering”) which is usually attached to a surveying pole as a target for a total station which emits a light beam at the device and calculates how long it takes to be reflected back in order to measure distance.
5. •
   An object having the shape of a geometrical prism.
6. •
   A cutting (“open passage at a level lower than the surrounding terrain, dug for a canal, railway, or road to go through”) or an embankment shaped like a prism or a number of prisms, such that its volume can be easily calculated.
7. •
   A crystal in which the faces are parallel to the vertical axis.
8. •
   (no longer used) A spectrum produced by light being refracted through a prism.

   • The beams, that thro' the Oriel shine, / Make prisms in every carven glass, […] — 1842