Webster's Revised Unabridged Dictionary · 1913

Holster

Holster , noun

[Dutch holster; skin to Anglo-Saxon heolstor den, cave, from helan to conceal, and to Icelandic hulstr case, Gothic hulistr covering, veil, huljan to cover. r17. See Hele to cover, Hell, and compare Housing, Houss.]

A leather case for a pistol, carried by a horseman at the bow of his saddle, or worn on the person suspended from a belt or shoulder strap.