What does "sly" mean?

Sly: Artfully cunning; secretly mischievous; wily. For my sly wiles and subtle craftiness, The litle of the kingdom I possess. Spenser.

Additional senses

  1. 2.Done with, and marked by, artful and dexterous secrecy; subtle; as, a sly trick. Envy works in a sly and imperceptible manner. I. Watts.
  2. 3.Light or delicate; slight; thin. [Obs.] By the sly, or On the sly, in a sly or secret manner. [Colloq.] "Gazed on Hetty's charms by the sly." G. Eliot. -- Sly goose (Zoöl.), the common sheldrake; -- so named from its craftiness. See Cunning.
  3. 4.Slyly. [Obs. or Poetic] Spenser.

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