Mortar

Mortar has several meanings:

Mortar (masonry), material used in masonry to fill the gaps between blocks and bind them together.
Mortar (weapon) fires shells at a much lower velocity and higher ballistic arc than other ordnance.
Mortar (firestop), hydraulic cementitious material used to firestop through-penetrations in wall and floor assemblies required to have a fire-resistance rating.
Mortar methods, discretization methods for partial differential equations.
Mortar and pestle, a vessel and implement used to crush or grind materials.
Mortarboard, a flattened type of headwear normally worn as part of academic dress.

See also