cathode ray

American  

noun

1. a flow of electrons emanating from a cathode in a vacuum tube and focused into a narrow beam.

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cathode ray Scientific  

1. A beam of electrons streaming from the negatively charged end of a vacuum tube (the cathode) toward a positively charged plate (the anode).

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Etymology

Origin of cathode ray

First recorded in 1875–80

Example Sentences

“Are we doing retro-futurism? Are we doing the the cathode ray tube screens? Are we doing all of that stuff that in 1979 felt super futuristic, and to us now, feels like 1979?” he says.

From Los Angeles Times • Aug. 12, 2025

The ’90s may have been a simpler time technologically, a fact underscored by the cathode ray tube television sets and first-generation Apple Macintosh computers that populate the photos.

From New York Times • Feb. 3, 2022

“It’ll come sooner,” he said, standing between the computers controlling the sluice gates and an old cathode ray tube TV set.

From Washington Post • Oct. 30, 2021

Thomson’s cathode ray tube showed that atoms contain small, negatively charged particles called electrons.

From Textbooks • Feb. 14, 2019

In 1920, the memorably named Philo T. Farnsworth conceived the cathode ray vacuum tube used in most all twentieth-century TV sets.

From "An Abundance of Katherines" by John Green