keep vs remain

keep is a noun but remain is not a noun.

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

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

Other hypernyms of keep include rest, stay.

keep (noun)	remain (noun)
the main tower within the walls of a medieval castle or fortress
a cell in a jail or prison
the financial means whereby one lives

keep (verb)	remain (verb)
prevent (food) from rotting	stay the same; remain in a certain state
prevent the action or expression of	be in a certain place and not leave
stick to correctly or closely	continue in a place, position, or situation
maintain by writing regular records	be left; of persons, questions, problems, results, evidence, etc.
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