Definition:
To modify video game software for one platform so it can be used on a different platform.
Also Known As: ported, porting, ports
Examples:
Donkey Kong Country 3 and Final Fantasy IV Advance were originally released for the Super Nintendo Entertainment System (SNES) and years later they were released again for the Game Boy Advance (GBA). The GBA is a completely different technology than the SNES so the software itself had to be “ported” to accommodate the GBA.
When you see the same game released for multiple platforms each version is a "port" of the game software.