unde - unsy
- undecidability
- undecipherable
- undeclared
- undeclared identifier
- undeclared symbol
- undeclared variable
- undefined
- undefined notion
- undefined symbol
- undefined variable
- undefined-length record
- undelete
- undent
- under
- under directory
- under way
- under-control operation
- underflow
- underflow error
- underflying computer
- underline
- underline character prompt
- underlining
- underload
- underlying computer
- underlying hardware
- underlying multi-mips
- underlying structure
- underscore
- undershoot
- underspecified cue
- understandability
- understander
- understanding
- undesired
- undesired event
- undesired modes
- undetectable
- undetectable error
- undetectable failure
