Modern invented variant of Sienna, an Italian place name and warm reddish-brown earth pigment color.
Xienna is a creative respelling of Sienna, a name that entered the English-speaking world as a direct borrowing from the Italian city of Siena in Tuscany — itself famous for its warm, rust-orange earth pigment known as "terra di Siena," or sienna, which has been a staple of painters' palettes since the Renaissance. To name a child Sienna — or Xienna — is to invoke that rich, warm, ochre world: the sunlit stone of medieval Italian architecture, the brushwork of Raphael and Duccio, the saturated palette of the earth itself.
The name Sienna gained significant momentum in the English-speaking world during the early 2000s, boosted in part by the visibility of British actress Sienna Miller, whose effortlessly stylish public persona gave the name associations of bohemian elegance. The Xienna spelling takes that established foundation and updates it visually, with the uncommon 'X' opening creating immediate distinction. In English, names beginning with X are rare enough to be inherently memorable, giving Xienna an eye-catching quality on a page or a classroom list.
The variant also signals something about contemporary naming culture's comfort with phonetic creativity — the understanding that a name can be invented or respelled without losing its connection to meaning and beauty. Xienna retains all the warmth of Sienna's artistic and geographic heritage while announcing, through that single letter substitution, that it belongs to its bearer alone.