"equator" in the noun sense
1. equator
an imaginary line around the Earth forming the great circle that is equidistant from the north and south poles
"the equator is the boundary between the northern and southern hemispheres"
2. equator
a circle dividing a sphere or other surface into two usually equal and symmetrical parts
Source: WordNet® (An amazing lexical database of English)
Princeton University "About WordNet®."
WordNet®. Princeton University. 2010.
View WordNet® License