| Abbreviation | Definition |
|---|---|
| NAC | N-acetylcarnosine |
| NAC | N-acetylcysteamine |
| NAC | National Addiction Centre |
| NAC | National Association of Cytologists |
| NAC | National Asthma Campaign |
| NAC | National Asthma Center |
| NAC | National Asthma Council Australia |
| NAC | near attack conformation |
| NAC | near attack conformer |
| NAC | needle aspiration cytology |
| NAC | Needs Assessment Checklist |
| NAC | Neighborhood Asthma Coalition |
| NAC | neoadjuvant chemotherapy |
| NAC | nipple-areolar complex |
| NAC | non-alcoholic cirrhosis |
| NACGP | National Association of Commissioning General Practitioners |
| NACPME | National Advice Centre for Postgraduate Medical Education |
| NAFHP | National Association of Fundholding Practices (now extinct) |
| NAG | N-acetylglucosamine |
| NAG | narrow-angle glaucoma |