Definition of "Equatorial" :

noun: a telescope whose mounting has only two axes of motion, one parallel to the Earth's axis and the other one at right angles to it

adjective: of or existing at or near the geographic equator

"Equatorial Africa."

adjective: of or relating to conditions at the geographical equator

"Equatorial heat."

adjective: of or relating to or at an equator

"Equatorial diameter."