One of the four galactic directions used on Starmaps in the Science Fiction role-playing game Traveller by Game Designer's Workshop.
It describes the direction away from the galactic core, the focal point of the galactic coordinate system. Maps are usually drawn with Coreward at the top, Trailing left, Spinward right and Rimward on the bottom of the map.
Rimward of the Third Imperium lies the Solomani Confederacy, a polity of humans from earth, which keeps an uneasy peace with the Third Imperium. What lies beyond is currently unknown by Imperial scientists, as the Solomani keep their exploration data to themselves.