Formulas
- Soul theorem
- Souček space
- Spacetime triangle diagram technique
- Spark (mathematics)
- Special case
- Special linear Lie algebra
- Spectral radius
- Spectral theorem
- Spectral theory of ordinary differential equations
- Sperner's lemma
- Sphere
- Spherical coordinate system
- Spherical design
- Spherical harmonics
- Spin-weighted spherical harmonics