aphelion

Etymology

around the Sun (3).]] A Greek form of New Latin aphēlium (whence English aphelium, now displaced), from Ancient Greek ἀπο- (apo-, prefix meaning ‘away, from, off’) + ἥλῐος (hḗlios, “the sun”) (ultimately from Proto-Indo-European *sóh₂wl̥ (“the sun”)) + -ον (-on, suffix forming some nouns), modelled after New Latin apogaeum (“apogee”). The plural form aphelia is from aphelion + -a (plural form of the suffix -on).

noun

1. (astronomy, also figurative) The point in the elliptical orbit of a comet, planet, or other astronomical object, where it is farthest from the Sun.