Mowed roughly on the outskirts of a field (6)
I believe the answer is:
meadow
'field' is the definition.
(a meadow is a field)
'mowed roughly on the outskirts of a' is the wordplay.
'roughly' indicates anagramming the letters.
'on the outskirts of' means one lot of letters goes inside another.
'mowed' is an anagram of 'medow'.
'medow' going around 'a' is 'MEADOW'.
(Other definitions for meadow that I've seen before include "Low ground near river" , "Area used for hay" , "Low-lying grassland" , "Hayfield" , "A field of rich grass" .)