SINCE 1828

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cathode ray

noun

Definition of cathode ray

1 cathode rays plural : the high-speed electrons emitted in a stream from the heated cathode of a vacuum tube
2 : a stream of electrons emitted from the cathode of a vacuum tube —usually used in plural

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First Known Use of cathode ray

1880

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See words that rhyme with cathode ray Britannica.com: Encyclopedia article about cathode ray

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