transcription, транскрипция: [ i-ˈlips, e- ]
noun
Etymology: Greek elleipsis
Date: circa 1753
1.
a. : oval
b. : a closed plane curve generated by a point moving in such a way that the sums of its distances from two fixed points is a constant : a plane section of a right circular cone that is a closed curve
2. : ellipsis
[
ellipse 1b: French, F' foci; P, P', P'' any point on the curve; FP + PF' = FP'' + P''F' = FP' + P'F'
]