For-demman

According to the Old English Dictionary:

for-demman

part, -demmende; p. de; pp. ed To shut or dam up; obtūrāre :-- Swá swá nædran deáfe, and fordemmende eáran heora sīcut aspĭdis surdæ, et obtūrantis aures suas, Ps. Spl. T. 57, 4. [Goth. faurdammjan to stop up: Ger. verdammen to embank, dam up.] for-demman