Apoapsis
The greatest radial distance of an Ellipse as measured from a Focus. Taking 
in the equation of anEllipse
gives the apoapsis distance
Apoapsis for an orbit
around the Earth 
is called apogee, and apoapsis for anorbit around the Sun is called aphelion. See also Eccentricity, Ellipse, Focus, Periapsis- Morrie's Law
- Morse Inequalities
- Morse Theory
- Morse-Thue Sequence
- Mortal
- Mortality Problem
- Morton-Franks-Williams Inequality
- Mosaic
- Moser
- Moser's Circle Problem
- Moss's Egg
- Motzkin Number
- Moufang Plane
- Mousetrap
- Mouth
- Moving Average
- Moving Ladder Constant
- Moving Sofa Constant
- Mrs. Perkins' Quilt
- Much Greater
- Much Less
- Mu Function
- Muirhead's Theorem
- Muller's Method
- Mulliken Symbols