equatorial

comparative more equatorial · superlative most equatorial

1. geographyOf, near, or relating to the equator.

   That plant is best suited to equatorial climates.

   1 more example

   In equatorial Ecuador, days and nights are almost the same length, and the sun goes down early.

   1990 August, Boyd Gibbons, “Missouri's Garden of Consequence”, in National Geographic, volume 178, number 2, page 130

2. Relating to the midline of any approximately spherical object.
3. chemistryof a bond, lying approximately in the plane of a ring, perpendicular to its axis

plural equatorials

1. astronomyA kind of telescope mounted so as to have two axes of motion at right angles to each other, one of them parallel to the axis of the Earth, and each carrying a graduated circle, one for measuring declination, and the other right ascension, or the hour angle, so that the telescope may be directed, even in the daytime, to any star or other object whose right ascension and declination are known.