defecator vs doer

defecator and doer both are nouns.

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

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

Other hypernyms of defecator include actor, worker.

defecator (noun)	doer (noun)
(obsolete) that which cleanses or purifies; especially, an apparatus for removing the feculencies of juices and syrups.	a person who acts and gets things done
a person who defecates