radiopaque dye vs dye

radiopaque dye and dye both are nouns.

Word	Noun	Adjective	Verb	Adverb
radiopaque dye	Yes	No	No	No
dye	Yes	No	Yes	No

As nouns, dye is a hypernym of radiopaque dye; that is, dye is a word with a broader meaning than radiopaque dye:

radiopaque dye: dye that does not allow the passage of X rays or other radiation; used to outline certain organs during X-ray examination
dye: a usually soluble substance for staining or coloring e.g. fabrics or hair

Other hypernyms of radiopaque dye include dyestuff.

radiopaque dye (noun)	dye (noun)
dye that does not allow the passage of X rays or other radiation; used to outline certain organs during X-ray examination	a usually soluble substance for staining or coloring e.g. fabrics or hair

radiopaque dye (verb)	dye (verb)
	color with dye
	color for microscopic study