The best replacement for ellipse is oval.

The best alternatives to ellipse are rated as following:
★★★★★  oval
★★★  circle
★★  hyperbola
★★  parabola
★  ellipsis
  lr baggs anthem
  miche pistard

Your alternative for ellipse is not listed? Suggest!
Speaking about ellipse, one probably shouldn't forget about foci.

Other search terms related to ellipse and their ratings are:
★★★★★ foci
★ major and minor axis
You have in mind a companion for ellipse and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of ellipse in all years. Click on graph for more.
ellipse
oval
circle