shady

adj.

[1]	indistinct , fly-by-night , 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
[2]	louche
[3]	fishy , funny , suspect , suspicious
[4]	shadowed , shadowy , umbrageous