Bartizan
BARTIZAN (according to the New English Dictionary, from bertizene, a Scottish corruption of "bratticing" or "brattishing," from O. Fr. bretesche, and meaning a battlemented parapet; apparently first used by Sir Walter Scott), a small battlemented turret, corbelled out at the angle of a wall or tower to protect a warder and enable him to see around him. Bartizans generally are furnished with oylets or arrow-slits.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)