Brother of Tamar, in the Bible (7)
I believe the answer is:
'brother of tamar in the bible' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for absalom that I've seen before include "David's boy" , "King David's rebellious son" , "Son of King David (Bible)" , "David's third son (OT)" , "King's rebellious son" .)