it's the equator.
the equator
The definition of zero latitude, from which all others are measured, is the equator.
The 0 line of latitude is the equator.
'Lines' of latitude are often called 'parallels' of latitude.
The name for the line of latitude is the Equator (the most important line of latitude).Others include:North PoleSouth PoleArctic CircleAntarctic Circle
Linesof latitude are also known as circles of latitude or parallels.
The imaginary line defined as zero latitude is usually referred to as the 'Equator'.
meridian
parallel
o degrees
equator
longitude