| OPS | operations; optical position sensor; osteoporosis-pseudolipoma syndrome; outpatient service; outpati... |
|---|---|
| OpScan | optical scanning |
| ORD | optical rotatory dispersion; oral radiation death |
| OSA | obstructive sleep apnea; Office of Services to the Aging; Optical Society of America; ovarian sectio... |
| CIA | chemiluminescent immunoassay; chymotrypsin inhibitor activity; colony-inhibiting activity; congenita... |