Firen-leahter (fyrn-)
Bosworth & Toller Anglo-Saxon Old English Dictionary - firen-leahter (fyrn-)
According to the Old English Dictionary:
es;
- firen-leahter (fyrn-)
- m. Great sin, crime :-- Bewépað eówere fyrnleahtras, Hml. Th. ii. 420, 16. Cf. syn-leabter. firen-leahter fyrn-