We don't have synonyms for stail yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are stain, sail and tail.
(n) :
(UK, obsolete) Alternative form of stale (“a long, thin handle, as of mops, rakes, etc.”). [(colloquial) Something stale; a loaf of bread or the like that is no longer fresh.]
(n) :
(UK, obsolete) Alternative form of stale (“a long, thin handle, as of mops, rakes, etc.”). [(colloquial) Something stale; a loaf of bread or the like that is no longer fresh.]