keep vs stay

keep and stay both are nouns.

Word	Noun	Adjective	Verb	Adverb
keep	Yes	No	Yes	No
stay	Yes	No	Yes	No

As verbs, stay is a hypernym of keep; that is, stay is a word with a broader meaning than keep:

Other hypernyms of keep include remain, rest.

keep (noun)	stay (noun)
the main tower within the walls of a medieval castle or fortress	continuing or remaining in a place or state
a cell in a jail or prison	(nautical) brace consisting of a heavy rope or wire cable used as a support for a mast or spar
the financial means whereby one lives	a thin strip of metal or bone that is used to stiffen a garment (e.g. a corset)
	a judicial order forbidding some action until an event occurs or the order is lifted
	the state of inactivity following an interruption

keep (verb)	stay (verb)
prevent (food) from rotting	stay the same; remain in a certain state
prevent the action or expression of	stop or halt
stick to correctly or closely	overcome or allay
maintain by writing regular records	fasten with stays
supply with necessities and support	be in a certain place and not leave
hold and prevent from leaving	stop a judicial process
retain possession of	dwell
look after; be the keeper of; have charge of	continue in a place, position, or situation
retain rights to	hang on during a trial of endurance
maintain for use and service
have as a supply
store or keep customarily
stop (someone or something) from doing something or being in a certain state
allow to remain in a place or position or maintain a property or feature
conform one's action or practice to
behave as expected during of holidays or rites
cause to continue in a certain state, position, or activity
supply with room and board
maintain in safety from injury, harm, or danger
fail to spoil or rot
continue a certain state, condition, or activity
to rear