speed up vs alter

speed up and alter both are verbs.

Word	Noun	Adjective	Verb	Adverb
speed up	No	No	Yes	No
alter	No	No	Yes	No

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

Other hypernyms of speed up include change, modify.

speed up (verb)	alter (verb)
move faster	remove the ovaries of
cause to move faster	become different in some particular way, without permanently losing one's or its former characteristics or essence
	cause to change; make different; cause a transformation
	insert words into texts, often falsifying it thereby
	make an alteration to