quadruplex vs four-fold

quadruplex and four-fold both are adjectives.

Word	Noun	Adjective	Verb	Adverb
quadruplex	No	Yes	No	No
four-fold	No	Yes	No	No

As adjectives, quadruplex and four-fold are synonyms defined as:

Other synonyms of quadruplex include fourfold, quadruple, quadruplicate.

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