Cielo is the Spanish and Italian word for "sky" or "heaven", from the Latin caelum, and is used as a term of endearment in both languages. As a given name it often shortens the Marian title María del Cielo. Cielo ranked number 895 in 2000, dropped out of the US top 1000 for many years and has returned with the nature-name trend: it re-entered in 2022 and reached number 795 in 2025, its best rank so far.