concealed weapon

Definition from Nolo’s Plain-English Law Dictionary

A weapon, particularly a handgun, which is kept hidden on one's person or under one's control (in a glove compartment or under a car seat). Carrying a concealed weapon is a crime unless the person with the weapon is a law enforcement officer or has a permit to carry a concealed weapon. Permits are usually issued by local law enforcement under guidelines that require the applicant to show the need for such a weapon, and require that the applicant have a record free of convictions, arrests, or improper activity.

Definition provided by Nolo’s Plain-English Law Dictionary.