A Bandon dump? (4)
I believe the answer is:
jilt
'dump?' is the definition.
(I've seen this before)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for jilt that I've seen before include "Throw over (lover)" , "Abandon at the altar" , "Cast aside capriciously" , "Unilaterally break off relationship with" , "Reject a lover without warning" .)