perihelion perihelian • perihelium · · · Info · Definitions · Antonyms · Characters · · perihelion · · Text Latin · · Script 10 · · Length Definitions · · · (noun) periapsis in solar orbit; the point in the orbit of a planet or comet where it is nearest to the sun. · · Noun Definition 1 Antonyms · · · aphelion · · Antonym 0 Characters · · e latin small letter e U+0065 h latin small letter h U+0068 i latin small letter i U+0069 l latin small letter l U+006C n latin small letter n U+006E o latin small letter o U+006F p latin small letter p U+0070 r latin small letter r U+0072