republishing vs publication

republishing and publication both are nouns.

Word	Noun	Adjective	Verb	Adverb
republishing	Yes	No	No	No
publication	Yes	No	No	No

As nouns, publication is a hypernym of republishing; that is, publication is a word with a broader meaning than republishing:

republishing: the act of publishing again
publication: the business of issuing printed matter for sale or distribution

Other hypernyms of republishing include publishing.

republishing (noun)	publication (noun)
the act of publishing again	the business of issuing printed matter for sale or distribution
	the act of issuing printed materials
	the communication of something to the public; making information generally known
	a copy of a printed work offered for distribution