Well, according to your beloved dictionary.com:So if you have a gun but never shoot anyone, it's not a weapon then?
https://dictionary.reference.com/browse/weapon
A weapon is
A gun never used to shoot anyone isn't a weapon since it's not being used in "attack or defense in combat, fighting, or war".any instrument or device for use in attack or defense in combat, fighting, or war, as a sword, rifle, or cannon.
A weapon is only a weapon when used as such. There are such things as "dual-purpose".