Abbot
Old English abbod, from ecclesiastical Latin abbas, abbat-, from Greek abbas ‘father’, from Aramaic 'abbā (see Abba1).
wiktionary
From Middle English abbot, abbod, abbed, from Old English abbat, abbad, abbod, from Latin abbās(“father”), from Ancient Greek ἀββᾶς(abbâs), from Aramaic אבא (’abbā, “father”). Doublet of abba, abbé, and bwana.
etymonline
abbot (n.)
Old English abbod "abbot," from Latin abbatem (nominative abbas), from Greek abbas, from Aramaic (Semitic) abba, title of honor, literally "the father, my father," emphatic state of abh "father." Spelling with -t is a Middle English Latinization. Originally a title given to any monk, later limited to the head of a monastery. The use as a surname is perhaps ironic or a nickname. The Latin fem. abbatissa is root of abbess. Related: Abbacy; abbatial; abbotship.