Cosymmedian Triangles
Extend the Symmedian Lines of a Triangle 
to meet theCircumcircle at 
, 
, 
. Then the Lemoine Point 
of is also theLemoine Point of 
. The Triangles and are cosymmedian triangles, and have the same Brocard Circle, second BrocardTriangle, Brocard Angle, Brocard Points, and Circumcircle.
- Span (Polynomial)
- Span (Set)
- Span (Vectors)
- Sparse Matrix
- Spearman Rank Correlation Coefficient
- Special Curve
- Special Function
- Special Linear Group
- Special Matrix
- Special Orthogonal Group
- Special Point
- Special Series Theorem
- Special Unitary Group
- Species
- Specificity
- Spectral Norm
- Spectral Power Density
- Spectral Radius
- Spectral Rigidity
- Spectral Theorem
- Spectrum (Operator)
- Spectrum Sequence
- Speed
- Spencer's 15-Point Moving Average
- Spence's Function