Humble, ultimately unimaginative sort of setter dropped (7)
I believe the answer is:
lowered
'dropped' is the definition.
(thesaurus)
'humble ultimately unimaginative sort of setter' is the wordplay.
'humble' becomes 'low' ('low' can be a synonym of 'humble').
'ultimately' suggests the final letters.
'sort of setter' becomes 'red'.
The final letter of 'unimaginative' is 'e'.
'low'+'e'+'red'='LOWERED'
(Other definitions for lowered that I've seen before include "Threatened" , "Let down gently" , "Moved something down" , "Brought down" , "Moved downwards" .)