ab > define

noun

A bachelor's degree in arts and sciences.
- synonyms: Bachelor of Arts, BA, Artium Baccalaurens
The eleventh month of the civil year; the fifth month of the ecclesiastical year in the Jewish calendar (in July and August.
- synonyms: Av
The muscles of the abdomen.
- synonyms: abdominal, abdominal muscle
The blood group whose red cells carry both the A and B antigens.
- synonyms: type AB, group AB

(n.) The fifth month of the Jewish year according to the ecclesiastical reckoning, the eleventh by the civil computation, coinciding nearly with August.

by Webster's Revised Unabridged Dictionary

(latin) AB - "Artium Baccalaureus" - Bachelor of Arts

(Military) AB stands for airbase

by Department of Defense Dictionary of Military and Associated Terms. 31 January 2011.