Source : Webster's Revised Unabridged Dictionary (1913)

Canny \Can"ny\, Cannei \Can"nei\, a. [Cf. Icel. kenn skilled,
   learned, or E. canny. Cf. {Kenn}.] [North of Eng. & Scot.]
   1. Artful; cunning; shrewd; wary.

   2. Skillful; knowing; capable. --Sir W. Scott.

   3. Cautious; prudent; safe.. --Ramsay.

   4. Having pleasing or useful qualities; gentle. --Burns.

   5. Reputed to have magical powers. --Sir W. Scott.

   {No canny}, not safe, not fortunate; unpropitious. [Scot.]

Source : WordNet®

canny
     adj : showing self-interest and shrewdness in dealing with others;
           "a cagey lawyer"; "too clever to be sound" [syn: {cagey},
            {cagy}, {clever}]
     [also: {canniest}, {cannier}]