[count] 1 : something (such as a gun, knife, club, or bomb) that is used for fighting or attacking someone or for defending yourself when someone is attacking you
▪ assault with a deadly weapon ▪ a concealed weapon ▪ chemical/biological weapons [=weapons that use dangerous chemicals, germs, etc.] ▪ weapons of mass destruction [=weapons that can destroy entire cities, regions, etc.] ▪ The police never found the murder weapon. [=the weapon used to commit murder]
2 : something (such as a skill, idea, or tool) that is used to win a contest or achieve something
▪ The pitcher's slider is his most effective weapon. ▪ a new weapon in the fight against cancer ▪ The mayor's campaign unleashed its secret weapon.
No really it's not fine unless your out to harm or kill someone.