[Middle English abesse, from Old French, from Late Latin abbātissa, from abbās, abbāt-, abbot; see abbot.]
ab·bot (āb'ət) n.
The superior of a monastery.
Abbr. Abb. Used as a title for such a person.
[Middle English abbod, from Old English, from Late Latin abbās, abbāt-, from Greek abbā, abbās, from Aramaic 'abbā, my father; see b in Semitic roots.]
(āb'ĭs) 
b in Semitic roots.]