- servolink
- short weight
- signal adjuster
- signal converter
- signal structure
- singing
- singing margin
- singing point
- shunted instrument
- siemens
- singular arc
- signal common
- siphon gauge
- sling psychrometer
- solid measure
- sonic log
- sorter
- slave
- span error
- span shift
- sounding vertical
- source reactor
- span
- spatial gid
- spectral analyzer
- speed indicator
- spintherometer
- spintometer
- spline gauge
- spring balance
- spring dynamometer
- square foot
- square meter
- square yard
- spiral balance
- spirit thermometer
- spline gage
- stability
- stability criterion
- stabilization
- stake net
- standard assembly
- standard compass
- standard measure
- standard nozzle
- standard protocol
- standard range
- standard thermometer
- standard weight
- standpipe piezometer
- square centimeter
- square decimeter
- square measure
- start routine
- state feedback
- state space
- state transition
- state variable
- state vector
- static accuracy
- station control
- statistical check
- steady state
- steam cone
- steam flowmeter
- steel straightedge
- step height
- step response
- step size
- step time
- steelyard
- steering compass
- stepwise change
- step scale
- stepless control
- stimulus
- straight edge
- straightforward
- subunit
- summing point
- strip chart
- substitution method
- superconducting thermometer
- superposition integral
- supply reel
- surface casing
- surface sensor
- surveying gid
- surveyor
- synchronous counter
- synthesis
- system deviation
- system motor
- tangent compass
- switching gate
- symbolic control
- sync line
- synchronizing line
- system control
- tachometric relay