lockmaster vs skilled workman

lockmaster and skilled workman both are nouns.

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

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

Other hypernyms of lockmaster include skilled worker, trained worker.

lockmaster (noun)	skilled workman (noun)
a worker in charge of a lock (on a canal)	a worker who has acquired special skills