This page is historical. Follow this link for the current version.
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 2015, no. 3. http://dmnes.org/2015/3/name/Abbatissa.