initialise vs split up

initialise is not a noun while split up is a noun.

Word	Noun	Adjective	Verb	Adverb
initialise	No	No	Yes	No
split up	Yes	No	Yes	No

As verbs, split up is a hypernym of initialise; that is, split up is a word with a broader meaning than initialise:

Other hypernyms of initialise include carve up, dissever, divide, separate, split.

initialise (noun)	split up (noun)
	an increase in the number of outstanding shares of a corporation without changing the shareholders' equity

initialise (verb)	split up (verb)
divide (a disk) into marked sectors so that it may store data	become separated into pieces or fragments
assign an initial value to a computer program	get a divorce; formally terminate a marriage
	discontinue an association or relation; go different ways
	separate into parts or portions