Boxer cheers maiden with rowing crew at bar (12)
I believe the answer is:
bantamweight
'boxer' is the definition.
(bantamweight is a kind of boxer)
'cheers maiden with rowing crew at bar' is the wordplay.
I cannot quite see how this works, but
'cheers' could be 'ta' (both can informally mean thank you) and 'ta' is found within the answer.
'maiden' could be 'm' (cricket abbreviation) and 'm' is located in the answer.
'with' could be 'w' (abbreviation) and 'w' is located in the answer.
'crew' could be 'eight' (an eight-person rowing team) and 'eight' is located in the answer.
'bar' could be 'ban' (I've seen this before) and 'ban' is present in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for bantamweight that I've seen before include "fighter" , "Boxing category" .)