knuckle duster vs weapon system

knuckle duster and weapon system both are nouns.

Word	Noun	Adjective	Verb	Adverb
knuckle duster	Yes	No	No	No
weapon system	Yes	No	No	No

As nouns, weapon system is a hypernym of knuckle duster; that is, weapon system is a word with a broader meaning than knuckle duster:

knuckle duster: (used in the plural) a small metal weapon; worn over the knuckles on the back of the hand
weapon system: any instrument or instrumentality used in fighting or hunting

Other hypernyms of knuckle duster include arm, weapon.

knuckle duster (noun)	weapon system (noun)
(used in the plural) a small metal weapon; worn over the knuckles on the back of the hand	any instrument or instrumentality used in fighting or hunting