| OA | obstructive apnea; occipital artery; occipito-anterior; occiput anterior; octanoic acid; ocular albi... |
|---|---|
| OSA | obstructive sleep apnea; Office of Services to the Aging; Optical Society of America; ovarian sectio... |
| OSAS | obstructive sleep apnea syndrome |
| PSA | parasternal short axis; pleomorphic salivary gland adenoma; polyethylene sulfonic acid; polysacchari... |
| SA | salicylic acid; saline [solution]; salt added; sarcoidosis; sarcoma; scalenus anticus; secondary ame... |