Artist repulsed by Coot's fatigued body? (4)
I believe the answer is:
army
'body?' is the definition.
(I have seen 'Military body ' mean 'army' so perhaps 'body' could also mean 'army')
'artist repulsed by coot's fatigued' is the wordplay.
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'repulsed' is a reversal indicator.
'by' says to put letters next to each other.
'coot's fatigued' becomes 'my' (I can't explain this - if you can you should give a lot more credence to this answer).
'ra' in reverse letter order is 'ar'.
'ar'+'my'='ARMY'
Can you help me to learn more?
(Other definitions for army that I've seen before include "Fighting unit" , "Collective term for caterpillars" , "A defence force" , "Large number (of ants?)" , "fighters" .)