| MEC | median effective concentration; middle ear canal; middle ear cell; minimum effective concentration |
|---|---|
| OCP | octacalcium phosphate; ocular cicatricial pemphigoid; oral case presentation; oral contraceptive pil... |
| OET | oral endotracheal tube; oral esophageal tube |
| OHI | Occupational Health Institute; operative hypertension indicator; oral hygiene index; Oral Hygiene In... |
| DFD | defined formula diets; developmental field defect; diisopropyl phosphorofluoridate |