Spillage of paint not appropriate (5)
I believe the answer is:
inapt
'not appropriate' is the definition.
(inapt means inappropriate or ill-fitting)
'spillage of paint' is the wordplay.
'paint' anagrams to 'INAPT'.
However, I am not clear how the anagram is indicated.
Can you help me to learn more?
(Other definitions for inapt that I've seen before include "It's clumsy" , "not fit for purpose" , "Not fit, unsuitable" , "Cartoon duck" , "Free from deceit" .)