(1):
(v. t.) Artfully cunning; secretly mischievous; wily.
(2):
(v. t.) Dexterous in performing an action, so as to escape notice; nimble; skillful; cautious; shrewd; knowing; - in a good sense.
(3):
(v. t.) Done with, and marked by, artful and dexterous secrecy; subtle; as, a sly trick.
(4):
(adv.) Slyly.
(5):
(v. t.) Light or delicate; slight; thin.