- unattended operation
- unbalanced bridge
- unbalance voltage
- uncorrected result
- ubbelohde viscometer
- ultimate position
- underdamped
- undershoot
- unit cell
- unit class
- unmeasurable small
- unsatisfactory
- uprange
- vacuum thermometer
- valuator
- value band
- value pattern
- vane meter
- vane wattmeter
- varhour meter
- variometer compass
- velocity constant
- velocity hole
- velocity servomechanism
- ventilation psychrometer
- vibration test
- viscosity manometer
- Venturi meter
- visrator
- visual display
- vortex flowmeter
- wait cycle
- wall humidistat
- water flowmeter
- wait control
- watt-hour
- wearout failure
- volcanic pipe
- voltage range
- voltage span
- volume counting
- volumetric heat
- weight unit
- wind vane
- wet thermometer
- workpiece program
- Y-sensitivity
- yaw simulator
- ZAF method
- Zahn viscometer
- zero elevation