| U&A | Usage & Attitudes 
| Others |
| u.a. | u. a.
| Others |
| U/A | Under Advisement
| Others |
| U/A | Under Agreement
| Others |
| U/A | Universal and Adult
| Others |
| U/A | UrinAnalysis
| Others |
| UA | A Unit Aide
| Others |
| uA | microAmpere
| Others |
| UA | Ukraine According
| Others |
| UA | Ultimate Adventure
| Others |
| UA | Ultimate Ancestor
| Others |
| UA | Ultimate Armor
| Others |
| UA | Ultimate Armour
| Others |
| UA | Ultimate Assasins
| Others |
| UA | Ultimate Assassins
| Others |
| UA | Ultrasonic Arteriography
| Others |
| UA | Umbilical Artery
| Others |
| UA | Unanieme Alcoholisten
| Others |
| UA | Unauthorised Authentics
| Others |
| UA | UnAuthorized
| Others |
| UA | Unauthorized Absence
| Others |
| UA | Unauthorized Authentic
| Others |
| UA | Unconditional Annihilation
| Others |
| UA | Under Anesthesia
| Others |
| UA | Under Armor
| Others |
| UA | Under Armored
| Others |
| UA | Undercover Agent
| Others |
| UA | Undercover Aura
| Others |
| UA | Undergraduate Assistant
| Others |
| UA | Undergraduate Association
| Others |
| UA | Undergraduate Assosciation
| Others |
| UA | Underground Access
| Others |
| UA | Underground Area
| Others |
| UA | Underlying Asset
| Others |
| UA | Underwriters Association
| Others |
| UA | Unholy Alliance
| Others |
| UA | Unicystic Ameloblastoma
| Others |
| UA | Unidad Alavesa
| Others |
| UA | Unified Agenda
| Others |
| UA | Unified Architecture
| Others |
| UA | Uniform Asymptotic
| Others |
| UA | Union Avoidance
| Others |
| UA | Unique Address
| Others |
| UA | Unit Administration
| Others |
| UA | Unit Attack
| Others |
| UA | Unit Authorization
| Others |
| UA | Unit Availability
| Others |
| UA | Unit of Account
| Others |
| UA | Unitary Authority
| Others |
| UA | Unitary Authority (Unitary Council)
| Others |
| UA | United Airlines
| Others |
| UA | United Almighty
| Others |
| UA | United America
| Others |
| UA | United Artists
| Others |
| UA | United Association
| Others |
| UA | United Atom
| Others |
| UA | Uniting Ambition
| Others |
| UA | Universal Access
| Others |
| UA | Universal Accessibility
| Others |
| UA | Universal Army
| Others |
| UA | Universe of Actions
| Others |
| UA | Universidad de Alicante
| Others |
| UA | University Affairs
| Others |
| UA | University Australia
| Others |
| UA | University of Alabama
| Others |
| UA | University of Arizona
| Others |
| UA | Unknown Armies
| Others |
| UA | Unlimited Access
| Others |
| UA | Unlimited Adventures
| Others |
| UA | Unlimited Ammo
| Others |
| UA | Unmanned Aircraft
| Others |
| UA | Unnumbered Acknowledge
| Others |
| UA | Unnumbered Acknowledgement
| Others |
| UA | Unreal Annihilation
| Others |
| UA | Unstable Angina
| Others |
| UA | Unstoppable Alliance
| Others |
| UA | Up Armor
| Others |
| UA | Update Attribute
| Others |
| UA | Update Australia
| Others |
| UA | Upper A
| Others |
| UA | Upper Airway
| Others |
| UA | Upper Arm
| Others |
| UA | Upper Austria
| Others |
| UA | Urban Agglomeration
| Others |
| UA | Urban Animals
| Others |
| UA | Urban Apps
| Others |
| UA | Urban Arcana
| Others |
| UA | Urbanized Area
| Others |
| UA | Urchin Account
| Others |
| UA | Uric Acid
| Others |
| UA | Urinalysis
| Others |
| UA | Urinary Albumin
| Others |
| UA | Urinary Analysis
| Others |
| UA | Urine analysis
| Others |
| UA | Uronic Acid
| Others |
| UA | User Acquisition
| Others |
| UA | User Agent
| Others |
| UA | User Authored
| Others |
| UA | Uterine Activity
| Others |
| UA | Uterine Artery
| Others |
| UA | Uterine Aspiration
| Others |