More trouble going topless (5)
I believe the answer is:
other
'more' is the definition.
('other' can be a synonym of 'more')
'trouble going topless' is the wordplay.
'trouble' becomes 'bother' ('bother' can be a synonym of 'trouble').
'going topless' means to remove the first letter.
'bother' with its first letter taken off is 'OTHER'.
(Other definitions for other that I've seen before include "Not the one mentioned" , "not like you" , "Distinct" , "else!" , "Different, disparate" .)