miller vs journeyman

miller and journeyman both are nouns.

Word	Noun	Adjective	Verb	Adverb
miller	Yes	No	No	No
journeyman	Yes	No	No	No

As nouns, journeyman is a hypernym of miller; that is, journeyman is a word with a broader meaning than miller:

Other hypernyms of miller include artificer, artisan, craftsman.

miller (noun)	journeyman (noun)
any of various moths that have powdery wings	a skilled worker who practices some trade or handicraft
machine tool in which metal that is secured to a carriage is fed against rotating cutters that shape it
someone who works in a mill (especially a grain mill)