Fácen-stæf

According to the Old English Dictionary:

fácn-stæf, es;

fácen-stæf

pl. nom. acc. -stafas; m. A deceitful or treacherous deed; nēquĭtia :-- Nalles fácnstafas fremedon they perpetrated no treacherous deeds, Beo. Th. 2041; B. 1018. facen-stæf