A-phēl’ion, n.

(a-fĕl’yun) (Synop., § 130), n.; pl. A-PHĒ/LĪ-A. [N. Lat. aphelium, from Gr. ἀπό, from, and ἥλιος, sun.] (Astron.) That point of a planet’s or comet’s orbit which is most distant from the sun, the opposite point being called the perihelion.