- noise mode
- noise modulation
- noise radiation
- noise source
- noise temperature
- nominal direction
- nominal fees
- nominal spacing
- nonlinear amplification
- nonrecurrent pulse
- noise diode
- noise figure
- noise generator
- noise peak
- noise reducer
- nominal amplitude
- nominal deviation
- non-access
- non-cyclic
- nonlinear oscillation
- nonresonant antenna
- normal install
- normal velocity
- normalization factor
- normalized angel
- nose bluntness
- nose shroud
- notch antenna
- notch filter
- nozzle diaphragm
- nuclear laser
- non-switch
- nonbusy hours
- nondirectional antenna
- nonlinear circuit
- nonlinear interpolation
- nonrecursive filter
- nonsaturted logic
- nonvoice communication
- normal range
- normal restart
- normal routing
- normal state
- normalized frequency
- nuclear battery
- number analysis
- number base
- number density
- numbering device
- numerical control
- numerical mode
- numerical table
- numerical word
- Null hypothesis
- null resources
- null system
- number converter
- numbering area
- numerical item
- numerical selector
- O network
- object distribution
- objectionable distortion
- objective grating
- obligated funds
- oblique incidence
- observed brightness
- obstacle gain
- occupancy rate
- occupied bandwidth
- ocean dynamics
- octal tube
- odd harmonic
- off condition
- off thyristor
- office communication
- office equipment
- offset feeds
- offset frequency
- offset ratio
- offshore platform
- octant error
- octary system
- odd-pulse
- OEM modem
- off board
- off chip
- off hook
- off transistor
- offset error
- OK signal
- omnidirectional aerial
- on-hold
- on-off
- one-electron
- one-loop
- on board
- online user
- onshore wind
- open clock