odd fellow vs doer

odd fellow and doer both are nouns.

Word	Noun	Adjective	Verb	Adverb
odd fellow	Yes	No	No	No
doer	Yes	No	No	No

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

odd fellow: someone regarded as eccentric or crazy and standing out from a group
doer: a person who acts and gets things done

Other hypernyms of odd fellow include actor, worker.

odd fellow (noun)	doer (noun)
someone regarded as eccentric or crazy and standing out from a group	a person who acts and gets things done