We don't have synonyms for non-word yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are nonword, non-work and n-word.
(n) :
Alternative spelling of non-word. [(linguistics) Any sequence of sounds or letters which is not considered to be a word, whether through an accidental gap (for example, phextapher-styphren) or through a systematic gap (for example, fssstpklyitnbkdv).]
(n) :
Alternative spelling of non-word. [(linguistics) Any sequence of sounds or letters which is not considered to be a word, whether through an accidental gap (for example, phextapher-styphren) or through a systematic gap (for example, fssstpklyitnbkdv).]