Mag is the short form of several words:
- Magazine, either as a periodical publication or a firearm component.
- Magnum, stemming from the latin word for large
- Magnet
- Magnification, in optical devices
- Magneto, an engine component (typically in the context of aviation)
- Magnesium alloy wheels, commonly called 'mags'
- Mines Advisory Group, a non-governmental organization (NGO) concerned with removal of debris of war (landmines, UXO etc)
- Magnesium float, a tool used in construction to smooth concrete
- The FN MAG Machinegun