This Syriac or Chaldee word is found three times in the New Testament (Mark 14:36; Rom. 8:15; Gal. 4:6), and in each case is followed by its Greek equivalent, which is translated “father.” It is a term expressing warm affection and filial confidence. It has no perfect equivalent in our language. It has passed into European languages as an ecclesiastical term, “abbot.”
Easton’s Bible Dictionary
Abba
Name meaningfather
Easton’s Bible Dictionary (1897), public domain. Text via Theographic Bible Metadata, CC BY-SA 4.0.