run around vs romp

run around is not a noun while romp is a noun.

Word	Noun	Adjective	Verb	Adverb
run around	No	No	Yes	No
romp	Yes	No	Yes	No

As verbs, run around and romp are synonyms defined as:

Other synonyms of run around include cavort, disport, frisk, frolic, gambol, lark, lark about, rollick, skylark, sport.

run around (noun)	romp (noun)
	gay or light-hearted recreational activity for diversion or amusement
	an easy victory
	a girl who behaves in a boyish manner