Eccentric Angle
The angle 
measured from the Center of an Ellipse to a point on the Ellipse.
- Dirichlet Series
- Dirichlet's Formula
- Dirichlet's Lemma
- Dirichlet's Principle
- Dirichlet's Test
- Dirichlet's Theorem
- Dirichlet Structure Constant
- Dirichlet Tessellation
- Dirty Beam
- Dirty Map
- Disc
- Disconnected Form
- Disconnectivity
- Discontinuity
- Discontinuous
- Discordant Permutation
- Discrepancy Theorem
- Discrete Distribution
- Discrete Fourier Transform
- Discrete Mathematics
- Discrete Set
- Discrete Uniform Distribution
- Discriminant
- Discriminant (Binary Quadratic Form)
- Discriminant (Elliptic Curve)