More tidy (6)
I believe the answer is:
neater
'more tidy' is the definition.
('neat' can be a synonym of 'tidy')
This is all the clue.
(Other definitions for neater that I've seen before include "More spick and span" , "Less untidy" , "Tidier" , "More tidy and uncluttered" , "Less messy" .)