| Abbreviations | Meaning |
 | ACTA | Assertive Community Treatment Association |
 | ACTA | Association Of Cardiothoracic Anaesthetists |
 | ACTA | Australian Chemical Trauma Alliance |
 | ACTM | Australasian College Of Tropical Medicine |
 | ACTTSA / CAAHTT | Association Canadienne Des Techniciens Et Technologistes En Santé Animale / Canadian Associatioon Of Animal Health Technologists And Technicians |
 | ACTUR | Automated Central Tumor Registry |
 | ACU | Association Of Clinicians For The Underserved |
 | ACUC | Associació Catalana D'Uròlegs De Comarques |
 | ACURP | American College Of Utilization Review Physicians |
 | ACVA | American College Of Veterinary Anesthesiologists |
 | ACVCP | American College Of Veterinary Clinical Pharmacology |
 | ACVECC | American College Of Veterinary Emergency And Critical Care |
 | ACVIM | American College Of Veterinary Internal Medicine |
 | ACVM | American College Of Veterinary Microbiologists |
 | ACVO | American College Of Veterinary Ophthalmologists |
 | ACVP | American College Of Veterinary Pathologists |
 | ACVPM | American College Of Veterinary Preventive Medicine |
 | ACVR | American College Of Veterinary Radiology |
 | ACVS | American College Of Veterinary Surgeons |
 | ACVT / TVAC | Association Canadienne Des Victimes De La Thalidomide / Thalidomide Victims Association Of Canada |
 | ADA | American Dental Association |
 | ADA | American Diabetes Association |
 | ADA | American Dietetic Association |
 | ADA | Americans With Disabilities Act |
 | ADA | Association Of Dialysis Advocates |
 | ADA | Australian Dental Association |
 | ADA CERP | American Dental Association Continuing Education Recognition Program |
 | ADA+C | Alberta Dental Association And College |
 | ADA+C | Alberta Dental Association And College |
 | ADAA | Alberta Dental Assistants Association |
 | ADAA | American Dental Assistants Association |
 | ADAA | Anxiety Disorders Association Of America |
 | ADAAF | American Dental Assistants Association Foundation |
 | ADAD | Alzheimer Disease And Associated Disorders [periodical] |
 | ADAL | Authorized Dental Allowance List |
 | ADAM | Animated Dissection Of Anatomy For Medicine (NLM) |
 | ADAPEI | Association Départementale De Parents Et Amis De Personnes Handicapées Mentales |
 | ADARA | Professionals Networking For Excellence In Service Delivery With Individuals Who Are Deaf Or Hard Of Hearing [Previously: American Deafness And Rehabilitation Association] |
 | ADARPEF | Association Des Anesthésistes Réanimateurs Pédiatriques D'Expression Française. Association Of French Speaking Paediatric Anaesthetists |
 | ADBS | Association Des Professionnels De L'Information Et De La Documentation |
 | ADC | Alzheimer's Disease Center |
 | ADC | Archives Of Diseases In Childhood |
 | ADC / CDA | Association Dentaire Canadienne / Canadian Dental Association |
 | ADC-ENSP | Association Des Directeurs Certifiés De L'ENSP (École Nationale De La Santé Publique) |
 | ADCA | Alcohol And Other Drugs Council Of Australia |
 | ADCN | Academic Dental Careers Network |
 | ADCRO | Association Pour Le Développement De La Chirurgie Réparatrice Et Orthopédique |
 | ADCS | Alzheimer's Disease Cooperative Study |
 | ADCS | Army Dental Care System |
 | ADD | Administration On Developmental Disabilities |