romper vs doer

romper and doer both are nouns.

Word	Noun	Adjective	Verb	Adverb
romper	Yes	No	No	No
doer	Yes	No	No	No

As nouns, doer is a hypernym of romper; that is, doer is a word with a broader meaning than romper:

Other hypernyms of romper include actor, worker.

romper (noun)	doer (noun)
a one-piece garment for children to wear at play; the lower part is shaped like bloomers	a person who acts and gets things done
a person who romps or frolics