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

Explanation

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.

Example Sentences

“They’re not pinpricks anymore,” said Nick Coleman, a consultant at Prism Strategic Intelligence, a London-based risk advisory firm.

From The Wall Street Journal • May 2, 2026

The new ownership is a venture led by Newport Beach real estate company Redwood West and Irvine developer Panattoni, in partnership with Prime Finance and Prism Places.

From Los Angeles Times • Mar. 13, 2026

Prism Hong Kong and Shanghai Ltd., which audited the accounts, said it lacked enough information to provide an opinion about the company’s ability to resolve its troubles.

From Seattle Times • Jul. 18, 2023

Ms. Haley also reported that she is a senior adviser at Prism Global Management, which is described on its LinkedIn page as a “US-based investment platform targeting growth-stage disruptive innovators in US and Asia.”

From New York Times • May 15, 2023

There’s Mom, Uncle Max, Prism, and even the kiss with Adam—I’m suffocating beneath the weight of life inexperience.

From "Starfish" by Akemi Dawn Bowman