- significant instant
- silicon detector
- silicon dioxide
- silicon foundry
- simple domain
- simple hypothesis
- simple mode
- simple parity
- simplex frequencies
- simplex mode
- simplex transmission
- simulated control
- simulated path
- simulated receiver
- simulated speech
- simulated system
- simulating routine
- simulation mode
- simulation run
- simulation test
- simulative generator
- simulcast broadcasting
- simultaneous carry
- simultaneous operation
- simultaneous processing
- simultaneous transmission
- SINAD ratio
- since-squared
- singeing machine
- singing
- singing suppressor
- single carry
- single channel
- single operation
- single pulse
- single rate
- shard band
- shared terminal
- sharing model
- sharp null
- sharp pulse
- sheath theory
- shipping route
- shock layer
- shock region
- short antenna
- short string
- shroud
- side wave
- shock test
- shock tube
- short card
- short channel
- short list
- short path
- side circuit
- sideband inference
- sideslip probe
- sieve cylinder
- single section
- single step
- singlet
- Sinking fund
- sidereal period
- sight assets
- sign test
- signal baseband
- signal carrier
- signal comparator
- signal component
- signal condition
- signal conditioner
- signal decision
- signal demulation
- signal detection
- signal digitizer
- signal distributor
- signal electrode
- signal extension
- signal fading
- signal generation
- signal generator
- signal injection
- signal interlocking
- signal label
- signal margin
- signal phase
- signal plate
- signal pulse
- signal regenerator
- signal restoration
- signal simulation
- signal simulator
- signal standards
- signal tracing
- signaling apparatus
- signaling code
- signaling information
- signaling method
- signaling reliability