Like or characteristic of a knave; given to knavery; trickish; fraudulent; dishonest; villainous; as, a knavish fellow, or a knavish trick
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 Dik"; "a wily old attorney"