Sly

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