Dictionary of Medieval Names
from European Sources

Giselwin m. Old High German gīsal 'pledge, hostage' + Old High German wini 'friend'.

France
Latin
c823 Gisloinus (nom) irminon-vol2 55, CE
Cite as: S.L. Uckelman. "Giselwin". In S.L. Uckelman, ed. The Dictionary of Medieval Names from European Sources, Edition 2019, no. 1. http://dmnes.org/2019/1/name/Giselwin.