maintenance vs keep

maintenance and keep both are nouns.

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

As nouns, keep is a hypernym of maintenance; that is, keep is a word with a broader meaning than maintenance:

Other hypernyms of maintenance include bread and butter, livelihood, living, support, sustenance.

maintenance (noun)	keep (noun)
activity involved in maintaining something in good working order	the main tower within the walls of a medieval castle or fortress
the act of sustaining life by food or providing a means of subsistence	a cell in a jail or prison
the unauthorized interference in a legal action by a person having no interest in it (as by helping one party with money or otherwise to continue the action) so as to obstruct justice or promote unnecessary litigation or unsettle the peace of the community	the financial means whereby one lives
means of maintenance of a family or group
court-ordered support paid by one spouse to another after they are separated

maintenance (verb)	keep (verb)
	prevent (food) from rotting
	prevent the action or expression of
	stick to correctly or closely
	maintain by writing regular records
	supply with necessities and support
	hold and prevent from leaving
	retain possession of
	look after; be the keeper of; have charge of
	retain rights to
	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