| NA | Avogadro constant or number; nalidixic acid; Narcotics Anonymous; network administrator; neuraminida... |
|---|---|
| OA | obstructive apnea; occipital artery; occipito-anterior; occiput anterior; octanoic acid; ocular albi... |
| SPA | salt-poor albumin; sheep pulmonary adenomatosis; sperm penetration assay; spinal progressive amyotro... |
| ACTS | acute cervical traumatic sprain or syndrome; advanced communication technology satellite; American C... |
| AMHT | automated multiphasic health testing |