Substantial order (4)
I believe the answer is:
tidy
I believe this is a double definition.
'substantial' is the first definition.
(thesaurus)
'order' is the second definition.
(tidying is a kind of ordering)
(Other definitions for tidy that I've seen before include "Clean and orderly" , "Considerable (sum); neat" , "Businesslike" , "Uncluttered" , "so substantial a sum" .)