I had to break up row, becoming more orderly (6)
I believe the answer is:
tidier
'more orderly' is the definition.
('tidy' is associated in meaning with 'orderly')
'i had to break up row' is the wordplay.
'i had' becomes 'I'd' (I'd).
'to break up' indicates putting letters inside (inserted letters break up or split the word).
'row' becomes 'tier' (tier is a kind of row).
'id' inserted within 'tier' is 'TIDIER'.
'becoming' acts as a link.
(Other definitions for tidier that I've seen before include "Trigger" , "'Neater, in better order (6)'" , "More trim" , "straightened up?" , "More neat and orderly" .)