news leak vs revelation

news leak and revelation both are nouns.

Word	Noun	Adjective	Verb	Adverb
news leak	Yes	No	No	No
revelation	Yes	No	No	No

As nouns, revelation is a hypernym of news leak; that is, revelation is a word with a broader meaning than news leak:

news leak: unauthorized (especially deliberate) disclosure of confidential information
revelation: the speech act of making something evident

Other hypernyms of news leak include disclosure, revealing.

news leak (noun)	revelation (noun)
unauthorized (especially deliberate) disclosure of confidential information	an enlightening or astonishing disclosure
	communication of knowledge to man by a divine or supernatural agency
	the speech act of making something evident