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Dictionary of Medieval Names
from European Sources

Abbatissa f. Latin abbatissa 'abbess'.

While this was more usually found as a title, there are a handful of English occurrences of it used as a given name.

Cite as: J. Uckelman, S.L. Uckelman. "Abbatissa". In S.L. Uckelman, ed. The Dictionary of Medieval Names from European Sources, Edition 2016, no. 2. http://dmnes.org/2016/2/name/Abbatissa.