| Acronym | Meaning |
| CAT | Category |
| CAT | Cabinet Advisory Team (UK) |
| CAT | Capital Acquisitions Tax (UK) |
| CAT | Capsule Ariane Technologies |
| CAT | Catapult |
| CAT | CECOM Accreditation Team |
| CAT | Central African Time (Gmt+0200) |
| CAT | Central Analysis Team |
| CAT | Central Artery-Tunnel (Boston Highway Construction Project) |
| CAT | Charges, easy Access and fair Terms (UK) |
| CAT | Citizens' Army Training |
| CAT | Citizenship Advancement Training (Philippines) |
| CAT | Civic Action Team |
| CAT | Civil Air Transport (CIA front airline during 1950s/1960s in Southeast Asia) |
| CAT | Civil Aviation Tribunal (Canada) |
| CAT | Civilian Augmented Training |
| CAT | Clear Air Turbulence |
| CAT | Climate Advisory Team (State of Washington) |
| CAT | Clinical Annual Training (US DoD) |
| CAT | Cloud Arrival Time |
| CAT | Cockpit Automation Technology |
| CAT | Collier Area Transit (Florida) |
| CAT | Combat AGE Team (US Air Force) |
| CAT | Combat Aircraft Technology |
| CAT | Combat Aircrew Training |
| CAT | Combat Application Tourniquet |
| CAT | Combat Auto Theft |
| CAT | Combined Acceptance Trials (Ships) |
| CAT | Combined Arms Team |
| CAT | Combined Arms Training |
| CAT | Command Action Team |
| CAT | Commercial Activity Tax (Ohio) |
| CAT | Common Admission Test (India) |
| CAT | Communauté de l'Agglomération Troyenne (French: Community of Troyes; now Communauté du Grand Troyes) |
| CAT | Communications Assist Team |
| CAT | Communications Assistance Center |
| CAT | Community-Aided Transport (public transporation; UK) |
| CAT | Competition Appeals Tribunal (UK) |
| CAT | Compliance Assessment Team |
| CAT | Computer-Assisted Testing |
| CAT | Conformance Acceptance Test |
| CAT | Connecticut Administrator Test (Connecticut State Department of Education) |
| CAT | Consolidated Airdrop Tool (US Air Force) |
| CAT | Container Anchorage Terminal |
| CAT | Contract Action Team |
| CAT | Contract Assistance Team |
| CAT | Contract Award Target |
| CAT | Contractor Acceptance Test |
| CAT | Control & Assessment Team |
| CAT | Conventional Arms Transfer |
| CAT | Corrective Action Team |
| CAT | Cost Analysis Team |
| CAT | Cost Apportionment Team |
| CAT | Cost Authority Target |
| CAT | Cougars and Teaching (Washington collaborative project) |
| CAT | Counter Assault Team (US Secret Service) |
| CAT | Course Achievement Test |
| CAT | Criminal Apprehension Team |
| CAT | Crisis Action Team |
| CAT | Customer Acceptance Test |