| Abbreviation | Definition |
|---|---|
| ARTS | Action Real Time Strategy |
| ASAP | Animation, Simulation, Assessment, and Problems |
| ASCI | ASTAR Scrabble Challenge International |
| ASGE | Advancement of Simulation and Gaming in Education |
| ASL | Advanced Squad Leader |
| ATB | Active Time Battle |
| ATC | Artist trading cards |
| ATDF | Anti Thottie Defense Force |
| ATGN | Australian Tabletop Gaming Network |
| ATHP | Authorized TeamSpeak Host Providers |
| ATT | Attack |
| ATTAC | Advanced Tradewars, Tactical Assault and Conquer |
| ATXI | Alliance Tournament XI (11) |
| AU | Alternate Universe |
| AU | Among Us |
| AUSEP | An Untitled Story Extension Project |
| AV | Armor Value |
| AVG | Animation Vfx Gaming |
| AVG | Austin Virtual Gaming |
| AVGA | Alberni Valley Gaming Association |