Sol (n.) Look up Sol at Dictionary.com
"the sun personified," mid-15c. (also in Old English), from Latin sol "the sun, sunlight," from PIE *s(e)wol-, variant of root *sawel- "the sun." French soleil (10c.) is from Vulgar Latin *soliculus, diminutive of sol; in Vulgar Latin diminutives had the full meaning of their principal words.