The story
- Anglo-Norman · derived fromtraiteresse
- Middle French · derived fromtraitresse
- Middle English · inherited fromtraitresse
- English todaytraitoress
From Middle English traitresse, traytouresse, from Middle French traitresse, Anglo-Norman traiteresse, treiteresce; equivalent to traitor + -ess.
Etymology from Wiktionary, CC BY-SA 4.0.