- spring buckle
- spring centre
- spring net
- starting field
- starting signal
- starting torque
- state ownership
- State recognition
- static hovering
- static inverter
- static stability
- station area
- station block
- station inspector
- station plan
- station platform
- station wagon
- stationary traffic
- stator vane
- Statute mile
- squeeze
- squeezer
- stability curve
- stabilization rail
- stabilizing fin
- stabilizing wheel
- stabling
- stand for
- staybolt
- steady flight
- steam separator
- steel gang
- steel section
- steel wheel
- steel wire
- steep vein
- steering angle
- steering wheel
- stem rake
- steady bearing
- steam generation
- steam raising
- steam traction
- steel
- steel vessel
- steep turn
- steer for
- stem
- step board
- stepped climb
- stern
- stern frame
- stern line
- stern pulpit
- stern tube
- stock car
- stoppage time
- stopping train
- stopway light
- storage charges
- storeroom
- stern flag
- stern light
- sternpost
- stock control
- stone embankment
- stop board
- stopping brake
- stopping distance
- stopway
- storage area
- stern thruster
- stiffener
- stop engines
- stop shoulder
- stopover
- stopping station
- storm sail
- stowage
- straight crossing
- straight crossover
- straight edge
- straight gear
- straight track
- strait
- strake
- strand
- stranded
- strap rail
- stevedore
- stone screening
- stop signal
- stopping lane
- stopping time
- stratocumulus
- street crossing
- street railway
- street track
- street warning
- streetcar schedule