round out vs alter

round out and alter both are verbs.

Word	Noun	Adjective	Verb	Adverb
round out	No	No	Yes	No
alter	No	No	Yes	No

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

Other hypernyms of round out include change, modify.

round out (verb)	alter (verb)
make bigger or better or more complete	remove the ovaries of
make round	become different in some particular way, without permanently losing one's or its former characteristics or essence
express as a round number	cause to change; make different; cause a transformation
fill out	insert words into texts, often falsifying it thereby
	make an alteration to