Search Result for "aphelion": 
Wordnet 3.0

NOUN (1)

1. apoapsis in solar orbit; the point in the orbit of a planet or comet that is at the greatest distance from the sun;


The Collaborative International Dictionary of English v.0.48:

Aphelion \A*phel"ion\ (?; 277), n.; pl. Aphelia. [Gr. ? + ? sun.] (Astron.) That point of a planet's or comet's orbit which is most distant from the sun, the opposite point being the perihelion. [1913 Webster]
WordNet (r) 3.0 (2006):

aphelion n 1: apoapsis in solar orbit; the point in the orbit of a planet or comet that is at the greatest distance from the sun [ant: perihelion]