Likely a variant of Savannah, originally a place and landscape term referring to open grassy plain.
Savanni is an elaborated, lyrical variant of Savannah, a name with roots in the Taíno language of the Caribbean. The original Taíno word "zabana" described a treeless plain or grassy flatland — the kind of vast, open landscape that early Spanish colonizers encountered and borrowed vocabulary to describe. The term passed into Spanish as "sabana" and into English as "savanna" or "savannah," eventually giving its name to the coastal Georgia city that became one of the American South's most storied urban landscapes.
Savannah entered widespread use as a given name in the United States during the nineteenth century, carried on a wave of place-name romanticism that also produced Georgia, Carolina, and Florence. The name evoked warmth, openness, and a kind of sun-drenched expansiveness. In the late twentieth century it experienced a major revival, appearing frequently in the top 100 American girls' names during the 1990s and 2000s.
Savanni adds an Italianate flourish — the doubled consonant and the final "i" lending it an operatic quality that feels simultaneously exotic and familiar. As a given name, Savanni appeals to parents who love the warmth and natural imagery of Savannah but want something less common, a personalization that signals both the pastoral roots of the original and an individual creative touch. It carries a sense of open horizons and natural grandeur, a name that seems to breathe fresh air.