The Collaborative International Dictionary of English v.0.48:

Tricky \Trick"y\, a.
   Given to tricks; practicing deception; trickish; knavish.
   [1913 Webster]

WordNet (r) 3.0 (2006):

tricky
    adj 1: not to be trusted; "how extraordinarily slippery a liar
           the camera is"- James Agee [syn: slippery, tricky]
    2: having concealed difficulty; "a catchy question"; "a tricky
       recipe to follow" [syn: catchy, tricky]
    3: marked by skill in deception; "cunning men often pass for
       wise"; "deep political machinations"; "a foxy scheme"; "a
       slick evasive answer"; "sly as a fox"; "tricky Dick"; "a wily
       old attorney" [syn: crafty, cunning, dodgy, foxy,
       guileful, knavish, slick, sly, tricksy, tricky,
       wily]

Moby Thesaurus II by Grady Ward, 1.0:

183 Moby Thesaurus words for "tricky":
   Herculean, Machiavellian, Machiavellic, abstruse, acute,
   ambidextrous, amoral, arch, arduous, artful, astute, awkward,
   beguiling, brutal, cagey, calculating, canny, catchy, cheating,
   chiseling, clever, collusive, complex, complicated, conscienceless,
   corrupt, corrupted, covinous, crafty, criminal, critical, crooked,
   cunning, cute, dark, debatable, deceitful, deceiving, deceptive,
   deep, deep-laid, delicate, delusive, delusory, demanding,
   designing, devious, difficile, difficult, diplomatic, dishonest,
   dishonorable, double, double-dealing, doubtful, dubious,
   duplicitous, evasive, exacting, fallacious, false, falsehearted,
   feline, felonious, finagling, fishy, formidable, foxy, fraudulent,
   furtive, guileful, hairy, hallucinatory, hard, hard-earned,
   hard-fought, hazardous, iffy, ill-got, ill-gotten, illusive,
   illusory, immoral, indirect, ingenious, insidious, intricate,
   inventive, jawbreaking, knotted, knotty, knowing, laborious, mean,
   misleading, no picnic, not easy, not kosher, operose, pawky,
   perfidious, playful, politic, prankish, pranksome, pranky,
   precarious, questionable, quirky, ready, resourceful, rigorous,
   risky, rocky, roguish, rotten, rough, rugged, scheming, sensitive,
   serpentine, set with thorns, severe, shady, shameless, sharp,
   shifty, shrewd, sinister, slick, slippery, sly, smooth, snaky,
   sneaky, sophistical, spiny, sportive, stealthy, steep, sticky,
   strategic, strenuous, subtile, subtle, supple, surreptitious,
   suspicious, tactical, thorny, ticklish, toilsome, touch-and-go,
   touchy, tough, treacherous, trick, trickish, tricksy, two-faced,
   uncertain, unconscienced, unconscientious, unconscionable,
   undependable, underhand, underhanded, unethical, unfair, unjust,
   unprincipled, unsavory, unscrupulous, unsportsmanlike,
   unstraightforward, uphill, vulpine, waggish, wary, wicked, wily,
   without remorse, without shame