- damped system
- damper guide
- damper valve
- damping network
- damping width
- dark current
- dark nebulae
- dash pot
- dead ground
- definition
- deflection Yoke
- defocused beam
- defrost
- defrost drain
- defrosting element
- defrosting grid
- defrosting system
- degraded minute
- degrease
- degree Rankine
- dehydration period
- deicing device
- deliquescence
- delivery air
- delivery duct
- delivery end
- delivery head
- delivery orifice
- delivery piping
- delivery pressure
- delivery side
- delivery speed
- delivery system
- delivery temperature
- delivery valve
- delta connection
- delta electron
- delta function
- delta mass
- delta modulation
- delta particle
- delta resonance
- delta voltage
- demagnetization coefficient
- demagnetization curve
- demagnetization process
- demagnetizing factor
- demagnetizing field
- death ray
- debris
- decade
- decay constant
- decay rate
- deceleration radiation
- decontaminating system
- decoupling
- deenergize
- deferent
- deficiency
- defocused picture
- deformation temperature
- defrost action
- defrost controller
- defrosting cycle
- defrosting effectiveness
- defrosting liquid
- defrosting procedure
- defrosting technique
- degaussing coil
- decade resistors
- decametric wave
- decanter
- decipher
- decomposition
- decontaminate
- decoupling network
- decrease
- decreasing pressure
- dedicated circuit
- deduction
- deep space
- defacement test
- deflecting electrode
- deflectivity
- deflector plate
- deflexion yoke
- defocusing
- defrost control
- defrost thermostat
- defroster coil
- defrosting circuit
- defrosting frequency
- defrosting position
- defrosting tube
- degeneracy
- degenerate gas
- degradation test
- degree Baume
- dehumidification technique
- dehumidifying apparatus