end vs break up

end is a noun but break up is not a noun.

Word	Noun	Adjective	Verb	Adverb
end	Yes	No	Yes	No
break up	No	No	Yes	No

As verbs, break up is a hyponym of end; that is, break up is a word with a more specific, narrower meaning than end:

As verbs, break up is a hyponym of end; that is, break up is a word with a more specific, narrower meaning than end:

end: have an end, in a temporal, spatial, or quantitative sense; either spatial or metaphorical
break up: close at the end of a session

end (noun)	break up (noun)
the part you are expected to play
(American football) a position on the line of scrimmage, designating players at each end of the defensive line
a piece of cloth that is left over after the rest has been used or sold
a final part or section
the state of affairs that a plan is intended to achieve and that (when achieved) terminates behavior intended to achieve it
the last section of a communication
the final stage or concluding parts of an event or occurrence
either extremity of something that has length
a boundary marking the extremities of something
the surface at either extremity of a three-dimensional object
one of two places from which people are communicating to each other
(football) the person who plays at one end of the line of scrimmage
a final state
the point in time at which something ends

end (verb)	break up (verb)
bring to an end or halt	laugh unrestrainedly
put an end to	break or cause to break into pieces
have an end, in a temporal, spatial, or quantitative sense; either spatial or metaphorical	come to an end
be the end of; be the last or concluding part of	separate (substances) into constituent elements or parts
	cause to go into a solution
	cause to separate
	close at the end of a session
	bring the association of to an end or cause to break up
	make a break in
	set or keep apart
	break violently or noisily; smash
	attack with or as if with a pickaxe of ice or rocky ground, for example
	release ice
	destroy the completeness of a set of related items
	take apart into its constituent pieces
	suffer a nervous breakdown
	disband
	to cause to separate and go in different directions
	discontinue an association or relation; go different ways