quadruplex vs quadruple

quadruplex is not a noun while quadruple is a noun.

Word	Noun	Adjective	Verb	Adverb
quadruplex	No	Yes	No	No
quadruple	Yes	Yes	Yes	No

As adjectives, quadruplex and quadruple are synonyms defined as:

Other synonyms of quadruplex include four-fold, fourfold, quadruplicate.

quadruplex (noun)	quadruple (noun)
	a quantity that is four times as great as another
	a set of four similar things considered as a unit

quadruplex (adjective)	quadruple (adjective)
having four units or components	four times as great or many
	having four units or components

quadruplex (verb)	quadruple (verb)
	increase fourfold