| ro | radius of orifice |
|---|---|
| UO | under observation; undetermined origin; urethral orifice; urinary output |
| UVO | vesico-ureteral orifice |
| tricuspid orifice | An atrioventricular opening which leads from the right atrium into the right ventricle of the heart. Synonym: ostium atrioventriculare dextrum, ostium venosum cordis. (05 Mar 2000) |
|---|---|
| external urethral orifice | The slitlike opening of the urethra in the glans penis, the external orifice of the urethra (in the female) in the vestibule, usually upon a slight elevation, the papilla urethrae. Synonym: ostium urethrae externum, external opening of urethra, meatus urinarius, orificium urethrae externum. (05 Mar 2000) |
| ureteric orifice | The opening of the ureter in the bladder, situated one at each lateral angle of the trigone; wide gaping of the ostium usually indicates vesicoureteral reflux. Synonym: ostium ureteris, orificium ureteris, ureteral meatus, ureteral opening. (05 Mar 2000) |