- shell model
- Sherring bridge
- shock front
- shock wave
- short circuit
- short sight
- shot noise
- shunt
- signal-to-noise ratio
- significant figure
- simple harmonic motion, SHM
- simple harmonic wave
- simple pendulum
- simulation
- simultaneity
- simultaneous events
- single channel analyzer
- single slit diffraction
- singlet state
- sinusoidal current
- siphon, syphon
- skin depth
- skin effect
- Slater determinant
- sliding friction
- sliding vector
- slit
- slow clock synchronization
- small vibration
- sodium lamp
- soft magnetic material
- solar cell
- solenoid
- solid
- solid-state counter
- solid-state laser
- solidification
- solidifying point
- solution
- solvation
- Sommerfeld elliptic orbit
- sonar
- sonometer
- sound
- sound level
- sound pressure
- sound source
- sound velocity
- sound wave
- source point