touch on vs refer

touch on and refer both are verbs.

Word	Noun	Adjective	Verb	Adverb
touch on	No	No	Yes	No
refer	No	No	Yes	No

As verbs, refer is a hypernym of touch on; that is, refer is a word with a broader meaning than touch on:

Other hypernyms of touch on include advert, bring up, cite, mention, name.

As verbs, touch on and refer are synonyms defined as:

Other synonyms of touch on include bear on, come to, concern, have to do with, pertain, relate, touch.

touch on (verb)	refer (verb)
restore by replacing a part or putting together what is torn or broken	think of, regard, or classify under a subsuming principle or with a general group or in relation to another
have an effect upon	have as a meaning
refer to or discuss briefly	make reference to
be relevant to	use a name to designate
	seek information from
	send or direct for treatment, information, or a decision
	be relevant to