| Acronym | Definition |
|---|
| RAT | Rating |
| RAT | Remote Administration Tool |
| RAT | Rough and Tumble (South African combat sport/art) |
| RAT | Ram Air Turbine |
| RAT | Read-A-Thon |
| RAT | Robust Audio Tool (teleconferencing) |
| RAT | Rock Abrasion Tool (NASA Mars Exploration Rover) |
| RAT | Remote Access Trojans (CERTs - Hacker Programs) |
| RAT | Router Audit Tool |
| RAT | Return Air Temperature |
| RAT | Remote Access Terminal |
| RAT | Rapid Assessment Team |
| RAT | Raduzhnyi (Russia) |
| RAT | Randall's Adventure & Training |
| RAT | Reject All Tobacco (Mississippi) |
| RAT | Rainier Agility Team |
| RAT | Readiness Assessment Tool |
| RAT | Renewal Agreement Travel |
| RAT | Rocket-Assisted Torpedo |
| RAT | Relative Accuracy Test |
| RAT | Recruit-at-Training |
| RAT | Rocket Assisted Takeoff |
| RAT | Roblox Assault Team (gaming clan) |
| RAT | Remote Associate Test |
| RAT | Ready Assets Trust (MLPFS) |
| RAT | Right Anterior Thigh |
| RAT | Road Anomalies Tour |
| RAT | Riders Association of Triumph Motorcycles |
| RAT | Recon Assault Team (video gaming clan) |
| RAT | Readiness Assessment Team |
| RAT | Reliability Assessment Test |
| RAT | Reliability Assurance Test |
| RAT | Reverse Arrangement Test |
| RAT | Routing Analysis Tool |
| RAT | Reprogramming Analysis Team (US Army) |
| RAT | Receiver Available Time |
| RAT | Reach-Around Technology |
| RAT | Radiological Assessment/Assistance Team |
| RAT | Release After Transmision (token ring, IEEE 802.5) |
| RAT | Report Authoring Tools |
| RAT | Right Angle Theorem |
| RAT | Ranges, Ammunition, and Targets |
| RAT | Remote Agent Token |
| RAT | Rapid Assault Tank (video game) |
| RAT | Redeployment Assistance Team |
| RAT | Robbery Apprehension Team |
| RAT | Raytheon Astor Team |
| RAT | Race Against Time |
| RAT | Radio Access Technology |
| RAT | Ritual Abuse-Torture (psychology) |
| RAT | Range and Taxi |
| RAT | Real Application Testing (software) |