/ɪˌmɪˈteɪʃən ˈfaɪərˌɑːm/ – Phrase
Definition: Vũ khí giả mạo.
A more thorough explanation: an object that looks like a gun or a rifle etc and which could be used to frighten someone, but which cannot shoot bullets and so is not dangerous
Example: He used an imitation firearm to threaten the woman during the robbery.