| Abbreviation | Definition |
|---|---|
| ACRE | Authentic Canadian Real Estate |
| ACSB | Associateship in Canadian Surety Bonding |
| ACSB | Association of Canadian Schools of Business |
| ACSUS | Association for Canadian Studies in the United States |
| ACTA | Association of Canadian Travel Agencies |
| ACTMD | Association Canadienne des Thérapeutes en Médecines Douces (French: Canadian Association of Therapis |
| ACTN | Association of Canadian Trauma Nurses |
| ACTS | Associated Canadian Theological Schools |
| ACUC | American Canadian Underwater Certifications |
| ACWA | Advancing Canadian Wastewater Assets |
| ACWC | All Canadian Wine Championships |
| ACWS | Atlantic Canada Wine Symposium |
| ACWWA | Atlantic Canada Water Wastewater Association |
| ADAPT | Arctic Development and Adaption to Permafrost in Transition |
| ADLC | Animal Defence League of Canada |
| ADMG | Algoma District Medical Group |
| AEAC | Adult Entertainment Association of Canada |
| AECB | Association for the Export of Canadian Books |
| AECBC | Advanced Education Council of British Columbia (Vancouver, British Columbia, Canada) |
| AECL | Atomic Energy of Canada Limited |