We don't have synonyms for stopword yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are shopworn, stop word and slopwork.
(n) :
Alternative form of stop word. [(computing) A word, usually one of a series in a stop list, that is ignored when searches are conducted on a database, search engine, etc.]
(n) :
Alternative form of stop word. [(computing) A word, usually one of a series in a stop list, that is ignored when searches are conducted on a database, search engine, etc.]