diode vs semiconductor diode

diode and semiconductor diode both are nouns.

Word	Noun	Adjective	Verb	Adverb
diode	Yes	No	No	No
semiconductor diode	Yes	No	No	No

As nouns, diode and semiconductor diode are synonyms defined as:

diode and semiconductor diode: a semiconductor that consists of a p-n junction

Other synonyms of diode include crystal rectifier, junction rectifier.

diode (noun)	semiconductor diode (noun)
a semiconductor that consists of a p-n junction	a semiconductor that consists of a p-n junction
a thermionic tube having two electrodes; used as a rectifier