- sly
- adj1. cunning, crafty, wily, artful, subtle, foxy. Sl. crazy like a fox, Scot, and North Eng. pawky; shrewd, astute, canny, sharp, knowing, Inf. cagey.2. covert, clandestine, undercover, stealthy, surreptitious, feline, back-alley, Canon Law. subreptitious; secret, hugger-mugger, hole-and-corner, closed-door, closet; furtive, underhand, underhanded, Inf. under the table or counter, back-room, sneaky, sneaking; devious, insidious, guileful, disingenuous, scheming, plotting, designing; tricky, crooked, dishonest, unethical, dishonorable, Inf. left-hand; shifty, slippery, Inf. shady.3. roguish, impish, puckish, waggish, elfish, prankish, mischievous; naughty, scampish, arch, Scot. hempy; playful, sportive, frolicsome, full or fond of mischief.n4. on the slyundercover, covertly, clandestinely, stealthily, surreptitiously, slyly, Scot. stownlins, Scot, and North Eng. pawkily; in secret, secretively, Inf. under the table or counter, Sl. on the quiet, Sl. on the Q.T.; furtively, underhandedly, sneakily, behind [s.o.'s] back, like a thief in the night.
A Note on the Style of the synonym finder. 2014.