diode vs zenerdiode

diode and zenerdiode both are nouns.

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

As nouns, zenerdiode is a hyponym of diode; that is, zenerdiode is a word with a more specific, narrower meaning than diode:

diode: a semiconductor that consists of a p-n junction
zenerdiode: a semiconductor diode that exhibits a sharp increase in reverse current at a well-defined reverse voltage: used as a voltage regulator

Other hyponyms of diode include LED, light-emitting diode, stabilitron, point-contact diode.

diode (noun)	zenerdiode (noun)
a semiconductor that consists of a p-n junction	a semiconductor diode that exhibits a sharp increase in reverse current at a well-defined reverse voltage: used as a voltage regulator
a thermionic tube having two electrodes; used as a rectifier