We don't have synonyms for nilla yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are villa, nill and nulla.
(n) :
(informal) Clipping of vanilla. [(countable) Any tropical climbing orchid of the genus Vanilla (especially Vanilla planifolia), bearing podlike fruit yielding an extract used in flavoring food or in perfumes.]
(n) :
(informal) Clipping of vanilla. [(countable) Any tropical climbing orchid of the genus Vanilla (especially Vanilla planifolia), bearing podlike fruit yielding an extract used in flavoring food or in perfumes.]