arsenal vs metalworks

arsenal and metalworks both are nouns.

Word	Noun	Adjective	Verb	Adverb
arsenal	Yes	No	No	No
metalworks	Yes	No	No	No

As nouns, metalworks is a hypernym of arsenal; that is, metalworks is a word with a broader meaning than arsenal:

Other hypernyms of arsenal include foundry.

arsenal (noun)	metalworks (noun)
a military structure where arms and ammunition and other military equipment are stored and training is given in the use of arms	factory where metal castings are produced
a place where arms are manufactured
all the weapons and equipment that a country has