| U-AMY | urinary amylase |
|---|---|
| UB | ultimobranchial body; Unna boot; upper back; urinary bladder |
| UC | ulcerative colitis; ultracentrifugal; umbilical cord; unchanged; unclassifiable; unconscious; undiff... |
| UCG | ultrasonic cardiography; urinary chorionic gonadotropin |
| UCI | unusual childhood illness; urethral catheter in; urinary catheter in |