- Strophulus (newborn) 779.89
- Struck by lighting 994.0
- Struma (see also Goiter) 240.9
- Strumipriva cachexia (see also Hypothyroidism) 244.9
- Strümpell-Marie disease or spine (ankylosing spondylitis) 720.0
- Strümpell-Westphal pseudosclerosis (hepatolenticular degeneration) 275.1
- Stuart's disease (congenital factor X deficiency) (see also Defect, coagulation) 286.3
- Stuart-Prower factor deficiency (congenital factor X deficiency) (see also Defect, coagulation) 286.3
- Students' elbow 727.2
- Stuffy nose 478.19
- Stump - see also Amputation cervix, cervical (healed) 622.8
- Stupor 780.09
- Sturge (-Weber) (-Dimitri) disease or syndrome (encephalocutaneous angiomatosis) 759.6
- Sturge-Kalischer-Weber syndrome (encephalocutaneous angiomatosis) 759.6
- Stuttering 307.0
- Sty, stye 373.11
- Subacidity, gastric 536.8
- Subacute - see condition
- Subarachnoid - see condition
- Subclavian steal syndrome 435.2
- Subcortical - see condition
- Subcostal syndrome 098.86