Excuse of boxer swinging this way and that? (5)
I believe the answer is:
alibi
'excuse' is the definition.
(excuse given by a suspect in an investigation)
'boxer swinging this way and that?' is the wordplay.
I cannot quite see how this works, but
'boxer' could be 'ali' (Muhammad Ali) and 'ali' is found in the answer.
'swinging' could be 'bi' (I've seen this in other clues) and 'bi' is found within the answer.
No letters remain.
This may be the basis of clue (or it may be nonsense).
'of' acts as a link.
Can you help me to learn more?
(Other definitions for alibi that I've seen before include "Story confirming innocence" , "Defence that one was somewhere else at the time of a crime" , "Plea of absence" , "it may help you to get off" , "Excuse - plea of being elsewhere" .)