| U | Uranium |
| UAProf | User Agent Profile |
| UART | Universal Asynchronous Reciever/Transmitter |
| UBM | Under-bump metallurgy |
| UCF | Universal Conduction Fluctuations |
| UCL | Upper confidence limit; Upper control limit |
| UDDI | Universal Description, Discovery and Integration |
| UDP | User Datagram Protocol |
| UEL | Upper explosive limit |
| UF | Ultra-Filtration |
| UFL | Upper Flammable Limit |
| UFPT | Ultra Fine Pitch Technology |
| UHB-LED | Ultra-High Brightness LED |
| UHF | UltraHigh Frequency |
| UHP | UltraHigh Purity |
| UHV | Ultra High Vacuum |
| UI | User Interface |
| UID | User IDentification |
| UIM | User Identification Module |
| ULA | Uncommitted logic array |
| ULPA | Ultra-low particulate air |
| ULSI | Ultra Large Scale Integrated (circuit) |
| UMID | Unique Material IDentifier |
| UML | Unified Modeling Language |
| UMPS | Modeling language for CPU cores |
| UMTS | Universal Mobile Telecommunications Service |
| Une | Unnilnonium |
| Uno | Unniloctium |
| Uns | Unnilseptium |
| UPH | Units per hour |
| UPI | Universal Programmable Peripheral Interface |
| UPS | Ultraviolet Photoelectron Spectroscopy; Uninterruptible Power Supply |
| UPW | UltraPure Water |
| URI | Uniform Resource Identifier |
| URL | Uniform Resource Locator |
| U/S | UltraSonic |
| USART | Universal Synchronous/Asynchronous Receiver/Transmitter |
| USB | Universal Serial Bus |
| USG | Undoped Silicate Glass |
| USIC | User-Specific Integrated Circuit |
| USOP | Ultra small outline package |
| UTF | Unicode Transformation Format |
| UTP | Unshielded Twisted Pair |
| UTPT | Unshielded Twisted Pair Transceiver |
| UTQFP | Ultra-Thin Quad Flat-Pack |
| UTRAN | UMTS Terrestrial Radio Access Network |
| UTS | Ultra-Thin Silicon |
| UTT | Unattenuated |
| UTW | Ultra-Thin Window for EDS detectors in TEMs. |
| UUT | Unit Under Test |
| UV | UltraViolet |
| UV-PROM | Ultra Violet Programmable Read Only Memory |
| V | Vanadium; Volt |
| VAC | Volts alternating current |
| VAD | Vertical Axial Deposition (Sumitomo) |
| VAR | Value added reseller |
| VASE | Variable angle spectroscopic ellipsometry |
| VB | Valence Band; Vertical Bridgman |
| VBAP | Voice Band Audio Processor |
| VBM | Valence Band Maximum |
| VCA | Voltage controlled amplifier |
| Vcc | Main Power Supply (in a circuit) |
| VCML | Vodafone Content Markup Language |
| VCO | Voltage Controlled Oscillator |
| VCSEL | Vertical Cavity Surface Emitting Laser |
| VCz | Vapor-pressure-controlled Czochralski |
| VDC | Volts direct-current |
| Vdd | Secondary power supply (in a circuit) |
| VDP | Van der Pauw |
| VDS | Vapor distribution system |
| VDSL | Very high bit-rate Digital Subscriber Line |
| Vee | Negative power supply (in a circuit) |
| VESA | Video Electronics Standards Association |
| VFD | Vacuum Fluorescent Display |
| VFEI | Virtual factory equipment interface |
| VGA | Variable Gain Amplifier |
| VGF | Vertical Gradient Freeze |
| VGS | Video Guidance Sensor |
| VHDL | VHSIC Hardware Description Language |
| VHF | Very high frequency |
| VHN | Vickers hardness number |
| VHP | Very high productivity |
| VHORG | Vertically and horizontally organized grid |
| VHS | Variable hard sphere |
| VHSIC | Very high-speed integrated circuit |
| VIGS | Virtual Induced Gap States |
| VISC | Video Instruction Set Computing |
| VLA | Very large array |
| VLE | Vapor levitation epitaxy |
| VLF | Vertical laminar flow |
| VLIW | Very Long Instruction Word |
| VLL | Video Lead Locator |
| VLSI | Very Large Scale Integrated (circuit) |
| VM | Virtual machine |
| VME | Versa micromodule extension; Virtual manufacturing enterprise |
| VML | Vector Markup Language |
| V-MOS | V-groove metal-oxide semiconductor |
| VMW | Vertically modulated well |
| VOC | Volatile organic compound |
| VoD | Video on Demand |
| VPD | Vapor phase desorption; Vapor phase decomposition |
| VPD-ICPMS | Vapor phase decomposition-inductively-coupled plasma mass spectroscopy |
| VPE | Vapour Phase Epitaxy |
| VPN | Virtual Private Network |
| Vpp | Programmable power supply (in a circuit) |
| VRAM | Video RAM |
| VRG | Vibratory Rate Gyro |
| VRP | Vi tl Rid P t t i |
