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

At first, we don’t quite know when we are — the TV sets are cathode ray, the phones are landlines and a cigarette machine sits in the town bar.

From Los Angeles Times • Apr. 28, 2026

In another, their mission appeared to involve breaking down old television sets and electronics, dropping bits of circuitry and cathode ray tubing into smaller plastic containers.

From Slate • Nov. 26, 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

The balloons float off, the streamers fly and the wide eyes of the world revel in the cathode ray tube’s sanctimony.

From New York Times • Jul. 15, 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