China 
Africa 
- Severe cutaneous adverse reactions
- Severe fever with thrombocytopenia syndrome
- Severe mental illness
- Severity of illness
- Seviteronel
- Sevoflurane
- Sewage
- Sewage sludge
- Sewers
- Sex addiction
- Sex assignment
- Sex chromosomes
- Sex cords
- Sex differentiation
- Sex education
- Sex hormone binding globulin
- Sex hormone binding protein
- Sex hormone receptor
- Sex hormone-binding globulin
- Sex hormones
- Sex life
- Sex linkage
- Sex pheromones
- Sex reassignment surgery
- Sex reversal
- Sex-lethal
- Sex-selective abortion
- Sexual abuse
- Sexual addiction
- Sexual and reproductive health and rights
- Sexual arousal
- Sexual arousal disorder
- Sexual assault
- Sexual attraction
- Sexual characteristics
- Sexual differentiation
- Sexual dimorphism
- Sexual dysfunction
- Sexual encounter
- Sexual exploration
- Sexual function
- Sexual harassment
- Sexual health clinic
- Sexual inversion
- Sexual jealousy
- Sexual masochism
- Sexual maturation
- Sexual medicine
- Sexual minority
- Sexual misconduct
- Sexual network
- Sexual norms
- Sexual obsessions
- Sexual orientation
- Sexual partner
- Sexual repression
- Sexual reproduction
- Sexual sadism
- Sexual satisfaction
- Sexual script theory
- Sexual selection
- Sexual stimulation
- Sexual violence
- Sexuality
- Sexually dimorphic nucleus
- Sezary cell
- SfM
- Sh3 domain
- Shadow
- Shadow effect
- Shaken baby syndrome
- Shallow breathing
- Sham surgery
- Shampoos
- Shared psychotic disorder
- Shark cartilage
- Shark liver oil
- Shave biopsy
- Shaving
- Shea butter
- Sheddase
- Sheehan's syndrome
- Sheep wool
- Shelf life
- Shell shock
- Shellac
- Shellfish allergy
- Shellfish poisoning
- Shelter-in-place
- Sheltered workshops
- Shelterin
- Shewanella
- Shewanella putrefaciens
- Shiatsu
- Shift work
- Shift work sleep disorder
- Shifting dullness
- Shiga toxin
- Shigella
- Shigella boydii
- Shigella dysenteriae
- Shigella flexneri
- Shigella sonnei
- Shigellosis
- Shikimate dehydrogenase
- Shikimate pathway
- Shikimic acid
- Shilajit
- Shin splints
- Shine-Dalgarno sequence
- Shingles
- Shingrix
- Shinrin-yoku
- Shivering
- Sho-saiko-to
- Shock
- Shock therapy
- Shock tube
- Shodhana
- Shoes
- Shogaol
- Shone's syndrome
- Short QT syndrome
- Short Syndrome
- Short acting insulin
- Short bowel syndrome
- Short chain fatty acids
- Short ciliary nerves
- Short circuits
- Short gastric arteries
- Short gastric veins
- Short hairpin RNA
- Short interspersed nuclear element
- Short rib–polydactyly syndrome
- Short stature
- Short tandem repeats
- Short term exposure limit
- Short term memory
- Short-chain dehydrogenase
- Short-term exposure limit
- Short-term memory
- Shortness of breath
- Shotgun lipidomics
- Shotgun proteomics
- Shotgun sequencing
- Shoulder
- Shoulder dystocia
- Shoulder girdle
- Shoulder impingement
- Shoulder impingement syndrome