Boxer of little importance (11)
I believe the answer is:
lightweight
I believe this is a double definition.
'boxer' is the first definition.
(I know that lightweight is a type of professional boxer)
'of little importance' is the second definition.
(I've seen this before)
(Other definitions for lightweight that I've seen before include "Insubstantial" , "of little importance" , "delicate" , "Of little substance" , "Fighter" .)