Paint splatter under accountant’s head (7)
I believe the answer is:
captain
'head' is the definition.
(captaining is a kind of heading)
'paint splatter under accountant's' is the wordplay.
I cannot quite understand how this works, but
an anagram of 'paint' is 'ptain' which is within the answer.
'accountant' could be 'ca' (abbreviation for chartered accountant) and 'ca' is present in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for captain that I've seen before include "Army rank" , "Chief" , "Naval commander" , "eg Hook, Cook" , "Skipper" .)