Eponyms beginning with S
- Siemens' syndrome I
- Siemens-Bloch pigmented dermatosis (Bruno Bloch)
- Siemens-Bloch-Sulzberger disease (Bruno Bloch)
- Siemens’ dermatosis
- Siemens’ syndrome
- Siemerling-Creutzfeldt syndrome
- Sieur's sign
- Sieur's test
- Sigault's operation
- Sigaultian section
- Signe de Bechterew-Mendel (French)
- Signe de Dance
- Signes de Verneuil (French)
- Signorelli's sign I
- Silberman's rule
- Silfverskiöld's syndrome
- Silver's syndrome
- Silver-Russell syndrome (Alexander Russell)
- Silverman syndrome
- Silverman's disease
- Silverman-Handmaker syndrome (Frederic N. Silverman)
- Silverman-Handmaker type of dyssegmental dysplasia
- Silvester's method
- Silvestroni-Bianco anaemia
- Silvestroni-Bianco syndrome