stun gun vs weapon system

stun gun and weapon system both are nouns.

Word	Noun	Adjective	Verb	Adverb
stun gun	Yes	No	No	No
weapon system	Yes	No	No	No

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

stun gun: a weapon designed to disable a victim temporarily by delivering a nonlethal high-voltage electric shock
weapon system: any instrument or instrumentality used in fighting or hunting

Other hypernyms of stun gun include arm, weapon.

stun gun (noun)	weapon system (noun)
a weapon designed to disable a victim temporarily by delivering a nonlethal high-voltage electric shock	any instrument or instrumentality used in fighting or hunting