| ARI | acute respiratory illness; airway reactivity index; anxiety reaction, intense |
|---|---|
| ARM | adrenergic receptor material; aerosol rebreathing method; ambulatory renal monitor; anorectal manome... |
| ARMS | adverse reaction monitoring system; amplification refractory mutation system |
| ASR | aldosterone secretion rate; antistreptolysin reaction |
| ASSR | adult situation stress reaction |