aequĭnoctĭālis

I. pertaining to the equinox, or the time of equal day and night, equinoctial: circulus, Varr. L. L. 9, § 24 Müll.: aestus, Sen. Q. N. 3, 28 (cf. aequinoctium fin.). horae, Plin. 2. 97. 99, § 216: meridies, Col. 1, 6, 2.