linesman vs skilled workman

linesman and skilled workman both are nouns.

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

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

Other hypernyms of linesman include skilled worker, trained worker.

linesman (noun)	skilled workman (noun)
a person who installs or repairs electrical or telephone lines	a worker who has acquired special skills
official (in tennis, soccer, football, etc.) who assists the referee in some way (especially by watching for out of bounds or offside)