- cylinder index
- cylindrical array
- cylindrical functions
- cylindrical harmonic
- cylindrical helicoid
- cylindrical projection
- cylindrical set
- cylindrical-conical
- cylindroid
- cylindroids
- cyphermail
- cyrix
- D format
- D-disk
- daily overview
- dark conduction
- dark discharge
- dark shading
- dark spot
- DASD queue
- dash line
- dashed link
- data aggregate
- data bank
- data bus
- data capture
- data carrier
- data center
- data clause
- data clock
- data concentrator
- data constant
- Data Control
- data deletion
- data file
- data flow
- data format
- data hierarchy
- data interface
- data jack
- data management
- data map
- data mining
- data modem
- data name
- data origin
- data points
- data preparation
- data quality
- data representation
- data rules
- data separation
- data set
- data sharing
- data signals
- data switching
- data system
- data tablet
- data tape
- data terminal
- data track
- data traffic
- data truncation
- data unit
- data warehousing
- DATABASE directory
- datagram
- date expression
- date format
- date literal
- date unit
- daughter board
- de-allocation
- deactivation
- dead position
- deadlock
- debugger flag
- debugging facility
- debugging phase
- debugging statement
- decapsulation
- deceleration time
- Decile
- decimal
- decimal notation
- decimal point
- decipherment
- declaration syntax
- declarative language
- declarative statement
- decoder
- decoding
- decoding gate
- decollate
- decollators
- decomposition group
- decompress
- decouple
- decrement
- decrement field