prism

American  

[priz-uhm] / ˈprɪz əm /

noun

1. Optics. a transparent solid body, often having triangular bases, used for dispersing light into a spectrum or for reflecting rays of light.

2. Geometry. a solid having bases or ends that are parallel, congruent polygons and sides that are parallelograms.

3. Crystallography. a form having faces parallel to the vertical axis and intersecting the horizontal axes.

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prism British  

/ ˈprɪzəm /

noun

1. a transparent polygonal solid, often having triangular ends and rectangular sides, for dispersing light into a spectrum or for reflecting and deviating light. They are used in spectroscopes, binoculars, periscopes, etc

2. a form of crystal with faces parallel to the vertical axis

3. maths a polyhedron having parallel, polygonal, and congruent bases and sides that are parallelograms

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prism Scientific  

/ prĭz′əm /

1. A geometric solid whose bases are congruent polygons lying in parallel planes and whose sides are parallelograms.

2. A solid of this type, often made of glass with triangular ends, used to disperse light and break it up into a spectrum.

3. A crystal form having 3, 4, 6, 8, or 12 faces parallel to the vertical axis and intersecting the horizontal axis.

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prism Cultural  

1. A solid figure in geometry with bases or ends of the same size and shape and sides that have parallel edges. Also, an object that has this shape.

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Discover More

A prism of glass (or a similar transparent material) can be used to bend different wavelengths of light by different amounts through refraction. This bending separates a beam of white light into a spectrum of colored light.

Etymology

Origin of prism

1560–70; < Late Latin prīsma < Greek prîsma literally, something sawed, akin to prī́zein to saw, prīstēs sawyer

Example Sentences

And yet his career should not be judged through the prism of these failures.

From BBC • Mar. 27, 2026

Kate Movius moved among a roomful of Los Angeles County sheriff’s deputies, passing out a pop trivia quiz and paper prism glasses.

From Los Angeles Times • Feb. 24, 2026

Much of EU policymaking is now being viewed through the prism of sovereignty.

From Barron's • Feb. 5, 2026

Though she was a trailblazing woman in the industry, she didn’t want her contributions to be seen through the prism of her gender.

From The Wall Street Journal • Jan. 1, 2026

On the coach’s nightstand sat a bowl of water, a stack of golden drachmas, a flashlight, and a glass prism for making rainbows.

From "The House of Hades" by Rick Riordan