showman vs promoter

showman and promoter both are nouns.

Word	Noun	Adjective	Verb	Adverb
showman	Yes	No	No	No
promoter	Yes	No	No	No

As nouns, showman and promoter are synonyms defined as:

showman and promoter: a sponsor who books and stages public entertainments

Other synonyms of showman include impresario.

showman (noun)	promoter (noun)
a sponsor who books and stages public entertainments	someone who is an active supporter and advocate
a person skilled at making effective presentations	a sponsor who books and stages public entertainments