Perihelion

{ Per′i‐hel″ion (?), Per′i‐he″li‐um (?), } n.; pl.Perihelia (#). [NL., fr. Gr. περί about, near + ἥλιοσ the sun.] (Astron.) That point of the orbit of a planet or comet which is nearest to the sun; — opposed to aphelion.