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Dictionary of Medieval Names
from European Sources

Bertisma f. Old High German beraht, Old Saxon berht 'bright' from Proto-Germanic *berhtaz + Latin -is(s)(i)ma, a superlative suffix.

France
Latin
c823 Bertisma (nom) irminon-vol2 34, Wan
Cite as: S.L. Uckelman. "Bertisma". In S.L. Uckelman, ed. The Dictionary of Medieval Names from European Sources, Edition 2018, no. 1. http://dmnes.org/2018/1/name/Bertisma.