- SUS
- SUV
- SV40
- SVC
- SVD
- SVEA
- SVG
- SVM
- SVO
- SVS
- SWAT model
- SWI-Prolog
- SWL
- SWMM
- SWOT analysis
- SWR
- SWR meter
- SWRL
- SaaS
- Sabatier reaction
- Sabbath
- Sabkha
- Sabot
- Saccades
- Saccharin
- Saccharomyces boulardii
- Saccule
- Sacral
- Sacral nerve stimulation
- Sacrifice zones
- Sacrificial anodes
- Sacrificial metal
- Sacroiliac joint
- Sacrospinous ligament
- Sacrotuberous ligament
- Saddle
- Saddle joint
- Saddle points
- Saddle-node bifurcation
- Safe operating area
- Safe-life
- Safe-life design
- Safety barriers
- Safety culture
- Safety engineer
- Safety engineering
- Safety factor
- Safety glass
- Safety instrumented system
- Safety lamp
- Safety life cycle
- Safety pharmacology
- Safety pins
- Safety valve
- Safety-critical
- Safety-critical systems
- Safflorite
- Saffron
- Safranal
- Safranin
- Sag
- Saga GIS
- SageMath
- Sagitta
- Sagittal
- Sagittal plane
- Sagittal suture
- Sagnac effect
- Saidi
- Sails
- Saint-Venant's principle
- Sal ammoniac
- Salen ligands
- Sales
- Salicin
- Salicylaldehyde
- Salicylaldoxime
- Salicylic acid
- Salience
- Salience network
- Saliency map
- Saline water
- Salinity
- Salinization
- Salinometer
- Salisbury screen
- Salivary glands
- Salmon
- Salmon calcitonin
- Salmonella Typhimurium
- Salmonella enterica
- Salmonellosis
- Salt
- Salt bridges
- Salt crust
- Salt domes
- Salt flats
- Salt glands
- Salt lakes
- Salt marshes
- Salt mines
- Salt mining
- Salt pans
- Salt spray test
- Salt tectonics
- Salt well
- Salt-and-pepper noise
- Saltation
- Saltatory conduction
- Salting in
- Salting out
- Saltpeter
- Saltwater intrusion
- Salvage
- Salvage therapy
- Samarium
- Samarium oxide
- Samba
- Sammon mapping
- Sample
- Sample and hold
- Sample complexity
- Sample mean
- Sample preparation
- Sample rate conversion
- Sample size
- Sample size determination
- Sample space
- Sample-rate conversion
- Sampled data system
- Sampling
- Sampling bias
- Sampling design
- Sampling distribution
- Sampling error
- Sampling fraction
- Sampling frame
- Sampling rate
- Sampling risk
- Sampling valve
- Sand
- Sand bath
- Sand boils
- Sand casting
- Sand engine
- Sand filter
- Sand mining
- Sand separator
- Sand sheet
- Sand waves