The accelerator cannon was a type of ship-mounted weapon system used by the Federation Starfleet, on starships that were in use around the turn of the 23rd century.

The weapons would work by running a nuclear warhead through a special charger, enhancing the missile's damage and accuracy. The missile would then be fired, at either warp or sublight speeds, a noticeable improvement over the old nuclear launch racks of the 22nd century, which were confined to sublight. (RPG reference book: Starship Construction Manual, 2nd Edition)

These cannons would be phased out by more efficient photon torpedo launcher systems in the mid-23rd century. (RPG reference book: Federation Ship Recognition Manual)