The 'half moon' crescent.

A half moon-shaped iron ornament 'Akali Nihangs' adorn on 'Damala' (turban) over the forehead to protect it. Half moon is symbol of Shiva, and Akali Nihangs see themselves as 'Shiv Swaroop' (Shiva's form). To Akali Nihangs, Shiva is a fellow 'Mahakali Nihang'.

Also refers to half moon-shaped arrowhead designed to target an opponent's bowstrings.

Also see 'Shiv Swaroop', 'Shiva'.