Sylvester's Determinant Identity
where
is the submatrix of 
formed by the intersection of the subset 
of columns and 
of rows.- Wiedersehen Manifold
- Wieferich Prime
- Wielandt's Theorem
- Wiener Filter
- Wiener Function
- Wiener-Khintchine Theorem
- Wiener Measure
- Wiener Space
- Wigner 3j-Symbol
- Wigner 6j-Symbol
- Wigner 9j-Symbol
- Wigner-Eckart Theorem
- Wilbraham-Gibbs Constant
- Wilcoxon Rank Sum Test
- Wilcoxon Signed Rank Test
- Wild Knot
- Wild Point
- Wilf-Zeilberger Pair
- Wilkie's Theorem
- Williams p+1 Factorization Method
- Wilson Plug
- Wilson Prime
- Wilson Quotient
- Douady's Rabbit Fractal
- Double Bubble