cathode-ray oscilloscope vs cathode-ray tube

cathode-ray oscilloscope and cathode-ray tube both are nouns.

Word	Noun	Adjective	Verb	Adverb
cathode-ray oscilloscope	Yes	No	No	No
cathode-ray tube	Yes	No	No	No

cathode-ray oscilloscope (noun)	cathode-ray tube (noun)
electronic equipment that provides visual images of varying electrical quantities	a vacuum tube in which a hot cathode emits a beam of electrons that pass through a high voltage anode and are focused or deflected before hitting a phosphorescent screen