refrain vs avoid

refrain is a noun but avoid is not a noun.

Word	Noun	Adjective	Verb	Adverb
refrain	Yes	No	Yes	No
avoid	No	No	Yes	No

As verbs, avoid is a hyponym of refrain; that is, avoid is a word with a more specific, narrower meaning than refrain:

Other hyponyms of refrain include fast, fast, keep off, teetotal.

refrain (noun)	avoid (noun)
the part of a song where a soloist is joined by a group of singers

refrain (verb)	avoid (verb)
choose not to consume	stay clear from; keep away from; keep out of the way of someone or something
resist doing something	refrain from certain foods or beverages
	declare invalid
	prevent the occurrence of; prevent from happening; to protect from or to keep away anything undesirable; to ward off
	refrain from doing something