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

1) See shadowy, 1, above. 2) indistinct, indefinite, questionable, doubtful, uncertain, unreliable, suspicious, suspect, dubious, shifty, disreputable; devious, tricky, slippery, underhand(ed) , unethical, unscrupulous, dishonourable, dishonest, Colloq fishy, crooked, bent, not (strictly) kosher: The minister's shady past will be revealed in the next issue of Tribune . She got involved with some shady character who had just come out of prison.