LED vs semiconductor diode

LED and semiconductor diode both are nouns.

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

As nouns, semiconductor diode is a hypernym of LED; that is, semiconductor diode is a word with a broader meaning than LED:

LED: diode such that light emitted at a p-n junction is proportional to the bias current; color depends on the material used
semiconductor diode: a semiconductor that consists of a p-n junction

Other hypernyms of LED include crystal rectifier, diode, junction rectifier.

LED (noun)	semiconductor diode (noun)
diode such that light emitted at a p-n junction is proportional to the bias current; color depends on the material used	a semiconductor that consists of a p-n junction