aphelion
Concise Oxford English Dictionary © 2008 Oxford University Press:
aphelion /apˈhiːlɪən/
▶noun (pl. aphelia /-lɪə/) Astronomy the point in a body's orbit at which it is furthest from the sun. The opposite of perihelion.
– origin C17: alt. of mod. L. aphelium, from Gk aph' hēlion ‘from the sun’.
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