AB vs Bachelor of Arts

AB and Bachelor of Arts both are nouns.

Word	Noun	Adjective	Verb	Adverb
AB	Yes	No	No	No
Bachelor of Arts	Yes	No	No	No

As nouns, AB and Bachelor of Arts are synonyms defined as:

Other synonyms of AB include Artium Baccalaurens, BA.

AB (noun)	Bachelor of Arts (noun)
the blood group whose red cells carry both the A and B antigens	a bachelor's degree in arts and sciences
a bachelor's degree in arts and sciences