Question

What is a small body that follows a highly elliptical orbit around the Sun

Answer 1

That could be a comet, or any one of the billions of meteoroids
moving in a cloud that's actually the remains of a shattered comet.

Answer 2

A small body of ice, rock, and dirt that follows a extremely elliptical orbit round the sun. a spherical region that surrounds the scheme and extends virtually halfway to the closest star. A small, on an irregular basis formed, rocky object that orbits the sun.

A estraterrestrial body is an icy tiny scheme body that, once passing on the brink of the Sun, warms and begins to unharness gases, a method known as outgassing.

This produces an evident atmosphere or coma, and typically additionally a tail.