sly

From Middle English sly, sley, sleigh, sleiȝ, from Old Norse slǿgr (“sly, cunning”, literally “capable of hitting or striking”), from Proto-Germanic *slōgiz (“lively, agile, cunning, sly, striking”), from Proto-Indo-European *slak- (“to hit, throw”).

Cognate with Icelandic slægur (“crafty, sly”), Norwegian Nynorsk sløg (“sly”). Related to sleight, slay. In all likelihood, however, unrelated with Saterland Frisian slau (“sly, crafty”), Dutch sluw (“sly, cunning”), Low German slu (“sly, cunning”), German schlau (“clever, crafty”). Doublet of sleight and slöjd