Lilli is a spelling variant of Lily or Lilly — the double-L, double-I version that signals a preference for softness and a slight departure from the standard form. In pet naming, spelling variations on common names often arrive through owner preference for a distinct look on a tag or registration form rather than through any meaningful sound difference. Lilli and Lily are phonetically identical.
The Lily Variant Landscape
Lilli, Lily, Lilly, Lillie, and Lili all exist in pet registries at various ranks. The standard form Lily is significantly more common, and the variants represent owners who wanted the name but with a personal signature. LIL-ee is well-established as a call name: two syllables, ending in a vowel, sounds warm and carries clearly. Domestic Shorthair cats attract Lily-family names disproportionately.
Flower Name Tradition
Lily names for pets draw from the broader flower-name tradition that includes Daisy, Violet, and Poppy. Flower names have been among the most consistent female pet names across decades because they are inherently soft, nature-connected, and impossible to read as aggressive or threatening. Lilli carries all of that with the added specificity of the doubled letters.
Counter-Reading: Spelling Maintenance
Anyone who cares about this specific spelling will spend their pet's life correcting it to Lilli from Lily or Lilly. Owners who don't mind casual respelling of the name lose nothing by registering the double-I version. The sound remains the same either way.