| Abbreviation | Definition |
|---|---|
| CAPS | Computer Assisted Passenger Screening |
| CAR | Caribbean Region |
| CARAT | Computer Aided Route Allocation Tool |
| CARAT | Congestion Avoidance and Reduction for Automobiles and Trucks |
| CARB | California Air Resources Board |
| CARD | Crash Avoidance Research Data File |
| CARF | Central Altitude Reservation Function |
| CART | Capital Area Rural Transportation |
| CART | Citizen Advocating Responsible Transport |
| CART | Cooperative Alliance for Regional Transportation |
| CARTA | Charleston Area Regional Transportation Authority |
| CAS | Commence Average Speed |
| CASA | Colombian American Service Association |
| CASA | Controller Automated Spacing Aid |
| CASC | Crushed Aggregate Subase Course |
| CASE | Continuing Automotive Service Education |
| CASHFORJUNKCARSINUSA | Cash For Junk Cars-Junk My Car helps people junk and recycle their vehicles for the best price offer |
| CASP | Commercial Auto Safety Program |
| CASS | Commercial Aviation Safety Survey |
| CASTO | California Association of School Transportation Officials |