— aphelian , adj.
/euh fee"lee euhn, euh feel"yeuhn, ap hee"lee euhn/ , n. , pl. aphelia /euh fee"lee euh, euh feel"yeuh, ap hee"lee euh/ .
Astron. the point in the orbit of a planet or a comet at which it is farthest from the sun. Cf. perihelion .
[ 1650-60; Hellenized form of NL aphelium aphélion ( diástema ) off-sun (distance), neut. of * aphélios (adj.), equiv. to ap- AP- 2 + héli ( os ) sun + -os adj. suffix. See APOGEE ]