| At | acidity, total; astatine; atrium, atrial |
|---|---|
| LA | lactic acid; large amount; laser angioplasty; late abortion; late antigen; latex agglutination; left... |
| RAI | radioactive iodine; radioactive isotope; resident assessment instrument; resting ankle index; right ... |
| RAR | rapidly adapting receptor; rat insulin receptor; retinoic acid receptor; right arm reclining; right ... |
| RB | radiation burn; rating board; rebreathing; reticulate body; retinoblastoma; right bronchus; right bu... |