rear sight

noun

the sight nearest the breech of a firearm.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for rear sight

Historical Examples of rear sight

The front sight must be seen through the middle of the rear-sight notch, the top being on a line with the top of the notch.
Manual for Noncommissioned Officers and Privates of Cavalry of the Army
War Department.

British Dictionary definitions for rear sight

rear sight

noun

the sight of a gun nearest to the breech

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012