| APC | acetylsalicylic acid, phenacetin, and caffeine; activated protein C; adenoidal-pharyngeal-conjunctiv... |
|---|---|
| ORS | olfactory reference syndrome; oral rehydration solution; oral surgery, oral surgeon; Orthopaedic Res... |
| CWHB | citrated whole human blood |
| OCP | octacalcium phosphate; ocular cicatricial pemphigoid; oral case presentation; oral contraceptive pil... |
| OET | oral endotracheal tube; oral esophageal tube |