rectifying valve vs rectifying tube

rectifying valve and rectifying tube both are nouns.

Word	Noun	Adjective	Verb	Adverb
rectifying valve	Yes	No	No	No
rectifying tube	Yes	No	No	No

As nouns, rectifying valve and rectifying tube are synonyms defined as:

rectifying valve and rectifying tube: a thermionic tube having two electrodes; used as a rectifier

Other synonyms of rectifying valve include diode.

rectifying valve (noun)	rectifying tube (noun)
a thermionic tube having two electrodes; used as a rectifier	a thermionic tube having two electrodes; used as a rectifier