craftsman vs skilled workman

craftsman and skilled workman both are nouns.

Word	Noun	Adjective	Verb	Adverb
craftsman	Yes	No	No	No
skilled workman	Yes	No	No	No

As nouns, skilled workman is a hypernym of craftsman; that is, skilled workman is a word with a broader meaning than craftsman:

Other hypernyms of craftsman include skilled worker, trained worker.

craftsman (noun)	skilled workman (noun)
a skilled worker who practices some trade or handicraft	a worker who has acquired special skills
a creator of great skill in the manual arts
a professional whose work is consistently of high quality