Try an easy diversion round the south (5)
I believe the answer is:
essay
'try' is the definition.
(essay can mean to try or attempt something)
'an easy diversion round the south' is the wordplay.
'diversion' indicates an anagram.
'round' is an insertion indicator.
'the south' becomes 's' (abbreviation).
'easy' is an anagram of 'esay'.
'esay' going around 's' is 'ESSAY'.
(Other definitions for essay that I've seen before include "Try - composition" , "Attempt - piece of writing" , "Make an effort to write one" , "example of Hazlitt's work" , "Composition; attempt" .)