definition of
shrewd

[1] #1 shrewd s. [astute, sharp] marked by practical hardheaded intelligence; "a smart businessman"; "an astute tenant always reads the small print in a lease"; "he was too shrewd to go along with them on a road that could lead only to their overthrow". wn

[2] #2 shrewd s. [calculating, calculative, conniving, scheming] used of persons; "the most calculating and selfish men in the community". wn