This man's covered with paint at work (8)
I believe the answer is:
thespian
'this' is the definition.
The definition suggests a singular noun which matches the answer.
'man's covered with paint at work' is the wordplay.
'man's' becomes 'he's' (he refers to a man).
'covered with' is an insertion indicator.
'at work' is an anagram indicator.
'paint' with letters rearranged gives 'tpian'.
'hes' going within 'tpian' is 'THESPIAN'.
Can you help me to learn more?
(Other definitions for thespian that I've seen before include "He paints (anag)" , "Dramatic performer" , "Player" , "Actor; relating to drama" , "cast member" .)