| Abbreviation | Definition |
|---|---|
| UCHD | Usual Childhood Diseases |
| UCJ | Unaided Clinical Judgment |
| UCKR | Uni-Compartment Knee Replacement |
| UCL | Ulnar Collateral Ligament |
| UCLV | Chloride Excretion rate |
| UCP | Uniform Customs And Practice |
| UCPG | University of Chicago Physicians Group |
| UCR | Un-Conditioned Reflex |
| UCR | Unconditioned reflex, response |
| UCR | Usual, Customary, and Reasonable |
| UCS | Unconditioned stimulus |
| UCS | Un-Conditioned Stimulus |
| UCS | Unconscious |
| UCTD | Undifferentiated Connective-Tissue Disease |
| UD | Ulnar deviation |
| UD | Under Developed |
| UD | Urethral Discharge |
| UDB | Universal Donor Blood |
| UDI | Urogenital Distress Inventory |
| UDP | Uridine Di- Phosphate |