duplication vs backup

duplication and backup both are nouns.

Word	Noun	Adjective	Verb	Adverb
duplication	Yes	No	No	No
backup	Yes	No	No	No

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

duplication: a copy that corresponds to an original exactly
backup: (computer science) a copy of a file or directory on a separate storage device

Other hyponyms of duplication include computer backup, counterpart, similitude, twin, match, mate.

duplication (noun)	backup (noun)
the act of copying or making a duplicate (or duplicates) of something	the act of providing approval and support
a copy that corresponds to an original exactly	(computer science) a copy of a file or directory on a separate storage device
	a musical part (vocal or instrumental) that supports or provides background for other musical parts
	someone who takes the place of another (as when things get dangerous or difficult)
	an accumulation caused by clogging or a stoppage