From Latin 'caelestis' meaning 'heavenly' or 'of the sky.'
Celestia derives from the Latin "caelestis," meaning "heavenly" or "of the sky," itself from "caelum" — the vault of heaven, the sky, the cosmos. The name is the feminine elaboration of Celeste, and both enjoyed particular favor in medieval Catholic Europe where names honoring the divine and celestial were common piety.
There was a Pope Celestine (a masculine form) — five of them, in fact — and the name branched into French as Céleste, Italian as Celestina, and Spanish as Celestina most famously through Fernando de Rojas's late-fifteenth-century tragicomedy "La Celestina," one of the foundational works of Spanish literature, in which the title character is a wily, unforgettable procuress — making Celestina paradoxically one of literature's most earthly celestial figures. In the English-speaking world, Celestia sat as an elegant rarity through the Victorian era, when astronomical enthusiasm and a love of Latinate names made it mildly fashionable. Its most significant modern cultural moment came through the animated series "My Little Pony: Friendship is Magic" (2010–2019), in which Princess Celestia is the immortal, benevolent co-ruler of Equestria who raises and lowers the sun each day — a character beloved for her warmth and wisdom by millions of children worldwide.
For parents today, Celestia carries a layered appeal: ancient enough to feel substantial, rare enough to feel distinctive, and sky-themed at a moment when cosmic and astral names — Luna, Nova, Lyra, Aurora — have never been more popular. It is a name that reaches upward.