indorser vs protagonist

indorser and protagonist both are nouns.

Word	Noun	Adjective	Verb	Adverb
indorser	Yes	No	No	No
protagonist	Yes	No	No	No

As nouns, protagonist is a hypernym of indorser; that is, protagonist is a word with a broader meaning than indorser:

Other hypernyms of indorser include admirer, booster, champion, friend, supporter.

indorser (noun)	protagonist (noun)
someone who expresses strong approval	a person who backs a politician or a team etc.
a person who transfers his ownership interest in something by signing a check or negotiable security	the principal character in a work of fiction