par·he·li·on (pär-hēlē-ən, -hēlyən)
n. pl. par·he·li·a (-hēlē-ə, -hēlyə)
A bright spot sometimes appearing at either side of the sun, often on a luminous ring or halo, caused by the refraction and reflection of sunlight by ice crystals suspended in the earth's atmosphere. Also called mock sun, sundog.
[Latin parēlion, from Greek : para-, beside; see PARA-1 + hēlios, sun; see sāwel- in the Appendix of Indo-European roots.]
par·helic (-hēlĭk) adj.
(click for a larger image)parhelion
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