ousting vs deposition

ousting and deposition both are nouns.

Word	Noun	Adjective	Verb	Adverb
ousting	Yes	No	No	No
deposition	Yes	No	No	No

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

ousting: the act of ejecting someone or forcing them out
deposition: the act of deposing someone; removing a powerful person from a position or office

Other hyponyms of ousting include dethronement.

ousting (noun)	deposition (noun)
the act of ejecting someone or forcing them out	the act of deposing someone; removing a powerful person from a position or office
	the act of putting something somewhere
	(law) a pretrial interrogation of a witness; usually conducted in a lawyer's office
	the natural process of laying down a deposit of something