noun
equatorial radius
Technical term in astronomy and geodesy; refers to the radius of a celestial body measured at the equator.
地球の赤道半径は約6378キロメートルです。
The Earth's equatorial radius is about 6378 kilometers.
Polar radius; the radius measured from the center to the pole, typically shorter than the equatorial radius for oblate spheroids.
Compound of 赤道 (equator) and 半径 (radius).