Dictionary of Medieval Names
from European Sources

Magner m. Old High German megin, magan 'strength, might, power' + Old High German heri 'host, army'.

France
Latin
1055 Magnerii (gen) StVdM-II 680, Magnerius (nom) ibid. 739, Mainerio (abl) ibid. 739; 1180 Mainerio (abl) RotScaNor p. 11; 1301 Mainerius (nom) MemPic-vol17 p. 217
Cite as: S.L. Uckelman. "Magner". In S.L. Uckelman, ed. The Dictionary of Medieval Names from European Sources, Edition 2017, no. 1. http://dmnes.org/2017/1/name/Magner.