Meaning

adjective showing the cunning or ingenuity or wickedness typical of a devil

adjective playful in an appealingly bold way

adverb in a playfully devilish manner

originFrom Middle English develissh, develyssh, equivalent to devil + -ish. Cognate with Saterland Frisian düvelsk, düüwelsk (“devilish”), West Frisian duvelsk (“devilish”), Dutch duivels (“devilish”), German Low German düvelsk (“devilish”), German teuflisch (“devilish”), Danish djævelsk (“devilish”), Swedish djävulsk (“devilish”), Norwegian djevelsk (“devilish”).

Etymology from Wiktionary, CC BY-SA 3.0