| AR | absolute risk; accounts receivable; achievement ratio; actinic reticuloid [syndrome]; active resista... |
|---|---|
| ARB | adrenergic receptor binder |
| ARIA | acetylcholine receptor-inducing activity; automated radioimmunoassay |
| ARM | adrenergic receptor material; aerosol rebreathing method; ambulatory renal monitor; anorectal manome... |
| ASGR | asialoglycoprotein receptor |