tailor vs dressmaker

tailor and dressmaker both are nouns.

Word	Noun	Adjective	Verb	Adverb
tailor	Yes	No	Yes	No
dressmaker	Yes	No	No	No

As nouns, dressmaker is a hypernym of tailor; that is, dressmaker is a word with a broader meaning than tailor:

Other hypernyms of tailor include garment-worker, garment worker, garmentmaker, adult male, man.

tailor (noun)	dressmaker (noun)
a person whose occupation is making and altering garments	a person who makes garments

tailor (verb)	dressmaker (verb)
adjust to a specific need or market
create (clothes) with cloth
style and tailor in a certain fashion