Basic spreading of dirty manure (11)
I believe the answer is:
rudimentary
'basic' is the definition.
(similar in meaning)
'spreading of dirty manure' is the wordplay.
'spreading of' is an anagram indicator.
'dirty'+'manure'='dirtymanure'
'dirtymanure' is an anagram of 'RUDIMENTARY'.
(Other definitions for rudimentary that I've seen before include "Limited to basics" , "Immature" , "Undeveloped" , "Basic" , "in the early stages" .)