I think you mean the two "tropic" lines.
They are at just over 23 degrees north and just over 23 degrees south of the equator.
prime meridian
The horizontal line that goes around the "waist" of the Earth is the Equator. The vertical line that goes vertically around the Earth, through the poles, is the Prime Meridian.
The horizontal line that goes around the "waist" of the Earth is the Equator. The vertical line that goes vertically around the Earth, through the poles, is the Prime Meridian.
It's called a latitude (But you asked for the name of the LINE that goes around the Earth like a parallel belt)
The equator is an imaginary line which indicates where the middle of the earth is and it goes around.
The imaginary line in the middle of the sky is called the Celestial Equator. It is basically just like the equator that goes around the earth. It is basically the dividing line of two halves of the earth.
The horizontal line that goes around the "waist" of the Earth is the Equator. The vertical line that goes vertically around the Earth, through the poles, is the Prime Meridian.
Equator
The imaginary line between the poles of the Earth around which the Earth spins is called the "axis of rotation".
Earth spins around its axis(or imaginary line from the north pole to the south pole) by gravity from earth itself and the surrounding planets.
LOL equater
The axis, or rotational axis. Pretty much, the line around which the earth spins.