sol

sol, solis is a third declension masculine noun and it barely uses a plural, because there is only one of it. Ablative sole.

Latin has no single verb for "to rise" and "to set" that you can hang a time on, so sunrise and sunset are built out of participles and nouns: sole oriente, "with the sun rising", an ablative absolute; solis occasus, "the sun's going down"; sub sole, under the sun. One thing to watch is the spelling collision with solus: solis here is the genitive singular of the sun, but solis is also the dative and ablative plural of "alone", and only context separates them. Descendants: Italian sole, Spanish sol, French soleil, from the diminutive soliculus.