- null line
- null list
- null matrix
- null modem
- null name
- null pattern
- null plane
- null pointer
- null polynomial
- null record
- null resource
- null ring
- null sequence
- null set
- null sphere
- null statement
- null subgroup
- null subring
- null system
- null vector
- number calculation
- number converter
- number cruncher
- number format
- number line
- number range
- number token
- number variable
- numbering
- numbering plan
- numeric data
- numeric item
- numeric operand
- numeric operation
- numeric pad
- numeric pager
- numeric printer
- numeric punch
- numeric value
- numeric variable
- numerical analysis
- numerical evaluation
- numerical expression
- numerical function
- numerical method
- numerical predicate
- numerical selection
- numlock
- nybble
- nybbte
- object authority
- object configuration
- object creation
- object description
- object distribution
- object handle
- object inline
- object library
- object machine
- object module
- object owner
- object routine
- object space
- object technology
- object variable
- objective
- oblique coordinates
- oblique helicoid
- oblique reflection
- oblique triangle
- observed value
- obsolescent feature
- obsolete element
- obsoleting indication
- obtain
- obturate
- obtuse
- obtuse angle
- obtuseness
- obviously
- occupied bandwidth
- occupy
- occurrence
- ocean liner
- octa
- octahedron
- octal code
- octave device
- odd substitution
- odds
- off-punch
- office building
- office links
- office name
- office products
- office suite
- offline storage
- OFT files
- ohm" law
- octahedral group