ə̇ˈlips, eˈ-, ēˈ- noun
( -s )
Etymology: alteration of ellipsis
1. : an elongated circle : a regular oval ; specifically : a closed plane curve generated by a point so moving that its distance from a fixed point divided by its distance from a fixed line is a positive constant less than 1
2. : ellipsis
[s]ellipse.jpg[/s] [
ellipse 1: French, F' foci; P, P', P'' any point on the curve; FP + PF' = FP'' + P''F' = FP' + P'F'
]