In geometry, a prism is a three-dimensional shape that has two bases that are parallel and the same size and shape. The prism's sides are all parallelograms. A classic pup tent is a triangular prism.

In optics, a prism is a piece of glass, quartz, plastic, or other material that can be used to refract light. A typical prism is triangular in shape, and when white light (like sunlight) is shown through it, the prism breaks the light into separate colors and displays it as a rainbow (color spectrum). Sir Isaac Newton experimented with prisms in the 1600s, and his work was the beginning of the modern period of both optics and the understanding of light.

Definitions of prism
  1. noun
    a polyhedron with two congruent and parallel faces (the bases) and whose lateral faces are parallelograms
    see moresee less
    show 5 types...
    hide 5 types...
    parallelepiped, parallelepipedon, parallelopiped, parallelopipedon
    a prism whose bases are parallelograms
    quadrangular prism
    a prism whose bases are quadrangles
    triangular prism
    a prism whose bases are triangles
    a rectangular parallelepiped
    a parallelepiped bounded by six similar faces (either rhombuses or parallelograms)
    type of:
    a solid figure bounded by plane polygons or faces
  2. noun
    optical device having a triangular shape and made of glass or quartz; used to deviate a beam or invert an image
    synonyms: optical prism
    see moresee less
    erecting prism
    a right-angled optical prism used to turn an inverted image upright
    type of:
    optical device
    a device for producing or controlling light
Word Family
F1 image

Express yourself in 25 languages

  • Learn immersively - no memorization required
  • Build skills for real-world conversations
  • Get immediate feedback on your pronunciation
Get started for $7.99/month