- default language
- default option
- default record
- default route
- default system
- default value
- defect analysis
- defective
- defective equation
- defective unit
- deferral mode
- defined operation
- definiteness
- deflate
- deflection coil
- deflection settlement
- deflective
- degenerate case
- degenerate quadratic
- decantation
- decatron scaler
- decay time
- december
- deciles
- decimal data
- decimal place
- decimal series
- decimal tab
- decision box
- decision circuit
- decision graph
- decision making
- decision point
- decision symbol
- declaration statement
- declarative sentence
- decoded
- decoding circuit
- decomposed
- decomposition
- decomposition space
- Decrease Indent
- decreasing sequence
- decurl
- dedicated circuit
- dedicated device
- dedicated link
- dedicated message
- dedicated server
- deduce from
- deduct
- deduction
- default
- default menu
- default page
- default rate
- default response
- default track
- defect group
- defective track
- defense
- defense-oriented
- deferent locus
- definability
- defined
- definition syntax
- deflection electrode
- deflection voltage
- deformation matrix
- deformation retract
- degenerate conic
- degenerate simplex
- degradation factor
- degree indeterminacy
- deionization potential
- dejag
- delay circuit
- delay equalizer
- delay network
- delay unit
- delayed
- delayed pulse
- delete button
- Demand function
- demand staging
- demarcation strip
- demo version
- democratic network
- demodulate
- demodulator channel
- demount
- denary
- dendroid
- denominate
- denote
- dense list
- dense ring
- denseness
- denumerable process
- deny