cover-up vs concealing

cover-up and concealing both are nouns.

Word	Noun	Adjective	Verb	Adverb
cover-up	Yes	No	No	No
concealing	Yes	Yes	No	No

As nouns, concealing is a hypernym of cover-up; that is, concealing is a word with a broader meaning than cover-up:

cover-up: concealment that attempts to prevent something scandalous from becoming public
concealing: the activity of keeping something secret

Other hypernyms of cover-up include concealment, hiding.

cover-up (noun)	concealing (noun)
concealment that attempts to prevent something scandalous from becoming public	the activity of keeping something secret

cover-up (adjective)	concealing (adjective)
	covering or hiding