- Sneezing
- Snellen chart
- Sniffing
- Snoezelen
- Snoring
- Snout reflex
- Snow blindness
- Soap
- Soap scum
- Soap substitutes
- Sober living house
- Sobriety
- Social Cognition and Interaction Training
- Social Hygiene Movement
- Social Interaction Anxiety Scale
- Social Phobia Inventory
- Social Readjustment Rating Scale
- Social Role Valorization
- Social Stories
- Social anxiety
- Social anxiety disorder
- Social cognition
- Social cognitive theory
- Social cohesion
- Social competence
- Social concept
- Social connectedness
- Social construction
- Social constructivism
- Social contagion
- Social control
- Social desirability bias
- Social determinants of health
- Social determinants of mental health
- Social disruption
- Social distancing
- Social dominance
- Social emotional development
- Social emotions
- Social environment
- Social epidemiology
- Social ethics
- Social grooming
- Social history
- Social immunity
- Social influence
- Social information processing
- Social innovation
- Social intelligence
- Social isolation
- Social justice
- Social learning theory
- Social marketing
- Social medicine
- Social model of disability
- Social narrative
- Social neuroscience
- Social norms
- Social perception
- Social phobia
- Social preferences
- Social prescribing
- Social psychiatry
- Social representations
- Social selection
- Social services
- Social skills
- Social stereotype
- Social stigma
- Social stress
- Social support
- Social withdrawal
- Socialization
- Socialized medicine
- Sociobiology
- Sociocultural context
- Socioemotional selectivity theory
- Sociotherapy
- Sociotropy
- Socratic method
- Socratic questioning
- Soda lime
- Sodium
- Sodium MRI
- Sodium adsorption ratio
- Sodium alginate
- Sodium arsenate
- Sodium arsenite
- Sodium aurothiomalate
- Sodium azide
- Sodium benzoate
- Sodium bicarbonate
- Sodium bisulfite
- Sodium bisulphite
- Sodium borate
- Sodium bromide
- Sodium butyrate
- Sodium calcium edetate
- Sodium calcium exchanger
- Sodium carbonate
- Sodium carboxymethyl cellulose
- Sodium channel blockers
- Sodium channels
- Sodium chlorate
- Sodium chloride
- Sodium chlorite
- Sodium citrate
- Sodium cyclamate
- Sodium dodecyl sulfate
- Sodium fluoride
- Sodium glucose cotransporter
- Sodium glucose cotransporter 2
- Sodium hexametaphosphate
- Sodium hyaluronate
- Sodium hypochlorite
- Sodium iodide
- Sodium ion
- Sodium lactate
- Sodium laureth sulfate
- Sodium metabisulfite
- Sodium metasilicate
- Sodium monofluorophosphate
- Sodium nitrate
- Sodium nitrite
- Sodium nitroprusside
- Sodium orthovanadate
- Sodium oxybate
- Sodium perborate
- Sodium percarbonate
- Sodium peroxide
- Sodium persulfate
- Sodium pertechnetate
- Sodium phenylbutyrate
- Sodium phosphate
- Sodium polyacrylate
- Sodium potassium ATPase
- Sodium retention
- Sodium salicylate
- Sodium selenate
- Sodium selenite
- Sodium silicate
- Sodium sulfate
- Sodium sulphate
- Sodium tetradecyl sulfate
- Sodium thiopental
- Sodium thiosulfate
- Sodium trimetaphosphate
- Sodium tungstate
- Sodium valproate
- Sodium zirconium cyclosilicate