slyly

[ slahy-lee ]
/ ˈslaɪ li /

adverb

in a deceitful manner; cunningly: They slyly plot to overthrow us.
in a roguish or mischievous way: Some were serious, while others slyly winked at the camera.

Origin of slyly

1350–1400 (def. 1); 1835–40 (def. 2); sly + -ly
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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