cover-up vs concealment

cover-up and concealment both are nouns.

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

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

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

Other hypernyms of cover-up include concealing, hiding.

cover-up (noun)	concealment (noun)
concealment that attempts to prevent something scandalous from becoming public	the activity of keeping something secret
	a covering that serves to conceal or shelter something
	the condition of being concealed or hidden