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Webster 1913 Edition

adv.

In an arch manner; with attractive slyness or roguishness; slyly; waggishly.

Archly

the maiden smiled.

Longfellow.

archly ‎(comparative more archly, superlative most archly)

- 1749, John Cleland, Fanny Hill: Memoirs of a Woman of Pleasure, Part 2
  Phoebe lay down by me, and ask'd me archly if, now that I had seen the enemy, and fully considered him, I was still afraid of him?

in an arch manner