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Webster 1913 Edition
Aphelion
A-phel′ion
(?; 277)
, Noun.
pl.
Aphelia
. [Gr. [GREEK] + [GREEK] 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.
Webster 1828 Edition
Aphelion
APHE'LION
,Noun.
That point of a planet's orbit which is most distant from the sun; opposed to perihelion.