lockmaster vs skilled worker

lockmaster and skilled worker both are nouns.

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

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

Other hypernyms of lockmaster include skilled workman, trained worker.

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