The Collaborative International Dictionary
Perihelium
Perihelion \Per`i*hel"ion\, Perihelium \Per`i*he"li*um\, n.; pl. Perihelia. [NL., fr. Gr. ? about, near + ? the sun.] (Astron.) That point of the orbit of a planet or comet which is nearest to the sun; -- opposed to aphelion.
Wiktionary
perihelium
n. perihelion