crafty (adj.)

mid-12c., crafti, "skillful, clever, learned," from Old English cræftig "strong, powerful," later "skillful, ingenious," acquiring after c. 1200 a bad sense of "cunning, sly, skillful in scheming," the main modern sense (but through 15c. also "skillfully done or made; intelligent, learned; artful, scientific"); see craft (n.) + -y (2). Perhaps to retain a distinctly positive sense, Middle English also used craftious as "skillful, artistic" (mid-15c.). Related: Craftily; craftiness.