Sly

прилагательное 1) коварный, ловкий, хитрый; пронырливый Например: a sly dog — хитрец, ловкач Синоним(ы): guileful, insidious 2) лукавый, озорной Синоним(ы): mischievous, naughty 3) скрытый, тайный Синоним(ы): secret, covert

Большой англо-русский словарь

Sly

adjective (slier or slyer; sliest or slyest) Etymology: Middle English sleighe, sli, from Old Norse slœgr; akin to Old English slēan to strike — more at slay 1. chiefly dialect a. wise in practical affairs b. displaying cleverness; ingenious 2. a. clever in concealing one's aims or ends; furtive Example: the sly fox b. lacking in straightforwardness and candor; dissembling Example: a sly scheme 3. lightly mischievous; roguish Example: a sly jest Example: a sly smileslyly also slily adverbslyness noun Synonyms: sly, cunning, crafty, wily, tricky, foxy, artful, slick mean attaining or seeking to attain one's ends by guileful or devious means. sly implies furtiveness, lack of candor, and skill in concealing one's aims and methods Example: a sly corporate raider. cunning suggests the inventive use of sometimes limited intelligence in overreaching or circumventing Example: the cunning fox avoided the trap. crafty implies cleverness and subtlety of method Example: a crafty lefthander. wily implies skill and deception in maneuvering Example: the wily fugitive escaped the posse. tricky is more likely to suggest shiftiness and unreliability than skill in deception and maneuvering Example: a tricky political operative. foxy implies a shrewd and wary craftiness usually involving devious dealing Example: a foxy publicity man planting stories. artful implies indirectness in dealing and often connotes sophistication or cleverness Example: elicited the information by artful questioning. slick emphasizes smoothness and guile Example: slick operators selling time-sharing.

Merriam-Webster's Collegiate Dictionary