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Dictionary of Medieval Names
from European Sources

Herois f. Old High German heri 'host, army' + Old Saxon widu, wido, Old High German witu 'wood'.

France
Latin
c823 Arois (nom) irminon-vol2 21, Palatiolum
Cite as: S.L. Uckelman. "Herois". In S.L. Uckelman, ed. The Dictionary of Medieval Names from European Sources, Edition 2018, no. 1. http://dmnes.org/2018/1/name/Herois.