- directional beam
- directional radiation
- directivity index
- directivity pattern
- directory number
- discharge action
- discharge air
- discharge chamber
- discharge cycle
- discharge duct
- discharge flue
- discharge key
- discharge pressure
- discharge pulsation
- discharge side
- discharge stroke
- discharge temperature
- discharge valve
- disconnecting switch
- disconnector
- discrete
- discrete spectrum
- discriminate
- discrimination
- disintegration constant
- disjunction
- disk capacitor
- dispersion effect
- displacement factor
- dissipated power
- dissipation line
- dissipative action
- distant measurement
- distiller
- distorted waveform
- distortion
- distributed constant
- distributed resistance
- distributed winding
- distributor
- distributor points
- directivity
- dirt trap
- disappear
- disc memory
- discharge
- discharge conditions
- discharge connection
- discharge detector
- discharge door
- discharge end
- discharge fan
- discharge gas
- discharge head
- discharge line
- discharge manifold
- discharge tubing
- discharge vapour
- discharging rate
- discharging stream
- discoidal
- disconnection
- discontinuous transition
- discrete semiconductor
- discriminating
- dislocation line
- displacement angle
- displacement law
- display section
- disruptive breakdown
- dissipated heat
- distillate
- distributed feedback
- distributed network
- distributed parameter
- distribution center
- diurnal variation
- divariant system
- division
- doctor
- dispergator
- dispersion
- dispersion formula
- dispersity
- dispersoid
- displacement
- displacement flux
- displacement rule
- display refrigeration
- disruptive distance
- dissipation power
- dissolved oil
- dissolved solid
- distance relay
- distinction
- distribution duct
- distribution main
- distribution pillar
- distribution probability
- diurnal effect