Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.
GERMAN
As described in historical dictionaries
Patronymica Britannica (1860)
GERMAN. GERIxUNE. Lat. gerimnus; of the same stock; a near kmsmau ; thus we say cousin-german for first-cousin. As a personal name it is of great antiquity in Britain, dating from St. German, the successful opponent of the Pelagian heresy in the fifth century. Possibly in some mstances it is derived from the country, like French, Irish, &c.
Surname type: Location or geographical feature
Origin: English
Region of origin: British Isles
Country of origin: England
Religion of origin: Christian
Language of origin: English