From Wiktionary, the free dictionary
From den (“the”) + lede (“loathsome one”), a noa-name for the Devil.
den lede c (genitive den ledes)
- (euphemistic) the Devil
- Synonyms: den onde, hin, hin håle, hin onde, skam
Fy för den lede!- Fie on the loathsome one! [curse expressing displeasure]