A weapon is an object such as a gun, a knife, or a missile, which is used to kill or hurt people in a fight or a war.
例句
...nuclear weapons.核武器
N-COUNT
(用于应付困境的)工具,手段
A weapon is something such as knowledge about a particular subject, which you can use to protect yourself or to get what you want in a difficult situation.
例句
I attack politicians with the one weapon they don't have, a sense of humor.我运用一种政客不具备的武器攻击他们,那就是幽默感。