reddish purple vs purple

reddish purple and purple both are nouns.

Word	Noun	Adjective	Verb	Adverb
reddish purple	Yes	No	No	No
purple	Yes	Yes	Yes	No

As nouns, purple is a hypernym of reddish purple; that is, purple is a word with a broader meaning than reddish purple:

Other hypernyms of reddish purple include purpleness.

reddish purple (noun)	purple (noun)
a shade of purple tinged with red	(Roman Catholic Church) official dress of a cardinal; so named after the Tyrial purple color of the robes
	a color between red and blue
	(in ancient Rome) position of imperial status

reddish purple (adjective)	purple (adjective)
	of a color intermediate between red and blue
	belonging to or befitting a supreme ruler
	excessively elaborate or showily expressed

reddish purple (verb)	purple (verb)
	color purple
	become purple