Mormal (n.) - a cancer or gangrene, a disease of the feet and shins.
He koude rooste, and sethe, and broille, and frye,
Maken mortreux, and wel bake a pye.
But greet harm was it, as it thoughte me,
That on his shyne a mormal hadde he.
For blankmanger, that made he with the beste.
- Chaucer, Geoffrey: The Canterbury tales (1387-1394)
The Middle-English Word of the Day is selected from Mayhew and Skeat's
"Concise Dictionary of Middle English."
As found on Greg Lindahl's website
The example text was found at the Middle English Collection of the University of Virginia Library.