A metal or plastic structure, usually notch-like in appearance, located at the top rear portion of a firearm and used in aiming at a target. The conventional style consists of a V-shaped or U-shaped blade into which has been cut a square, U-shaped, or V-shaped notch. When a firearm is in line with a target the front sight is seen to lie in the center of the rear sight notch. Also called a rear sight.
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