The Oxford Thesaurus An A-Z Dictionary of Synonyms - fishy adj.

1) piscine, fishlike, piscatory, piscatorial: On the fishmonger's slab lay an array of fishy offerings, only a few of which I could recognize. 2) dubious, doubtful, questionable, unlikely, far-fetched, suspicious, not kosher, peculiar, odd, queer, strange, suspect, improbable, implausible, Colloq shady, funny: There is something fishy about this deal.