Ge-mýþ

According to the Old English Dictionary:

ge-mýþ

pl. n. The mouth of a river; ostium fluminis :-- Æt ðám gemýðum Tyne streámes juxta ostium Tini fluminis, Bd. 5, 6; S. 618, 28: Cod. Dipl. Kmbl. iii. 48, 26. [O. H. Ger. ge-mundi ostia.] ge-myþ