equator

noun4

1. •
   An imaginary great circle around Earth, equidistant from the two poles, and dividing earth's surface into the northern and southern hemispheres.

   • Baishui is about as close to the equator as Tampa, Florida. — 2018
2. •
   A similar great circle on any sphere, especially on a celestial body, or on another reasonably symmetrical three-dimensional body.
3. •
   The midline of any generally spherical object, such as a fruit or vegetable, that has identifiable poles.

   • Slice the onion through the equator.
4. •
   The celestial equator.