Dictionary of Medieval Names
from European Sources

Daguin m. Old Saxon, Old Dutch dag, Old High German tag 'day' + Old High German wini 'friend'.

France
Middle French
1388 Daguenet thierry
Cite as: J. Uckelman, S.L. Uckelman. "Daguin". In S.L. Uckelman, ed. The Dictionary of Medieval Names from European Sources, Edition 2016, no. 4. http://dmnes.org/2016/4/name/Daguin.