How is something "objectively a weapon, though? Is this a weapon or just a weird stick that gets waved around in the Australian House of Representatives? Is this a sword or is it just a tool for cutting things, the larger equivalent of a dinner knife?

Is the knife in a Swiss Army Knife a weapon? What about the other parts of it? If I make a dagger with fork-tine in the hilt, so I can stab people and eat spaghetti with the same tool, is it a weapon? What if somebody makes the same exact implement, but with the intent to use the dagger for cutting really big spaghetti noodles and not people?