urge on vs advocate

urge on is not a noun while advocate is a noun.

Word	Noun	Adjective	Verb	Adverb
urge on	No	No	Yes	No
advocate	Yes	No	Yes	No

As verbs, advocate is a hyponym of urge on; that is, advocate is a word with a more specific, narrower meaning than urge on:

Other hyponyms of urge on include hurry, rush, bear on, push, preach.

urge on (noun)	advocate (noun)
	a person who pleads for a cause or propounds an idea
	a lawyer who pleads cases in court

urge on (verb)	advocate (verb)
force or impel in an indicated direction	push for something
spur on or encourage especially by cheers and shouts	speak, plead, or argue in favor of