China 
Africa 
- Spondylodiscitis
- Spondylolisthesis
- Spondylolysis
- Spondylopathy
- Spondylosis
- Spondylosis deformans
- Spongiosis
- Spongy tissue
- Spontaneous abortion
- Spontaneous alternation
- Spontaneous bacterial peritonitis
- Spontaneous breathing trial
- Spontaneous conception
- Spontaneous coronary artery dissection
- Spontaneous fission
- Spontaneous mutation
- Spontaneous orgasm
- Spontaneous pneumothorax
- Spontaneous remission
- Sporadic hemiplegic migraine
- Spores
- Sporobolomyces
- Sporogenesis
- Sporopollenin
- Sporosarcina
- Sporotrichosis
- Sporozoites
- Sports
- Sports drinks
- Sports medicine
- Sports nutrition
- Sporulation
- Spot reduction
- Spot tests
- Spotted fever
- SprD
- Sprained ankle
- Sprains
- Sprengel's deformity
- Sprifermin
- Sprint
- Sprouting
- Spurling's test
- Sputnik V
- Sputum
- Sputum culture
- Squalamine
- Squalane
- Squalene
- Squalene epoxidase
- Squalene monooxygenase
- Squalene synthase
- Squamosal bone
- Squamosal suture
- Squamous cell
- Squamous cell carcinoma
- Squamous cell lung carcinoma
- Squamous cell papilloma
- Squamous epithelium
- Squamous intraepithelial lesion
- Squamous metaplasia
- Squaric acid
- Squats
- Squint
- Src family kinase
- Src homology domain
- Sstr1
- Sstr2
- Sstr3
- Sstr4
- Sstr5
- Stab wounds
- Stabilization
- Stabilizers
- Stabilizing agents
- Stable cell
- Stable isotope labeling by amino acids in cell culture
- Stable nucleic acid lipid particle
- Stachyose
- Stadiometer
- Stage hypnosis
- Stage specific embryonic antigen 3
- Stagnant water
- Stainless steel
- Stains
- Stair climbing
- Standard anatomical position
- Standard curve
- Standard of care
- Standard of practice
- Standardized mortality ratio
- Standardized tests
- Standing
- Standing frame
- Standing wheelchair
- Stanford Protocol
- Stanford Sleepiness Scale
- Stanford V
- Stanford-Binet Intelligence Scale
- Stanford-Binet Intelligence Scales
- Stanine
- Stannosis
- Stannous fluoride
- Stanozolol
- Stapedius
- Stapedius muscle
- Stapedotomy
- Stapes
- Staphylococcal food poisoning
- Staphylococcal scalded skin syndrome
- Staphylococcus
- Staphylococcus aureus
- Staphylococcus epidermidis
- Staphylococcus haemolyticus
- Staphylococcus hominis
- Staphylococcus lugdunensis
- Staphylococcus saprophyticus
- Staphylococcus simulans
- Staphylokinase
- Staphyloma
- Staphyloxanthin
- Staple foods
- Stapled hemorrhoidectomy
- Stapled hemorrhoidopexy
- Starch
- Starch granules
- Stargardt disease
- Staring
- Starling equation
- Start codon
- Start triage
- Startle response
- Starvation
- Starvation response
- Stasis dermatitis
- Stat2
- State dependent learning
- State dependent memory
- State of emergency
- Stathmin
- Static light scattering
- Static mixers
- Static stretching
- Statins
- Stationary phase
- Statistical analysis
- Statistical dispersion
- Statistical genetics
- Statistical hypothesis testing
- Statistical inference