Lethargy resulting from some heated rows in Essex (10)
I believe the answer is:
drowsiness
'lethargy' is the definition.
(I've seen this before)
'some heated rows in essex' is the wordplay.
'some' indicates a hidden word (some parts of the word are used).
'DROWSINESS' is hidden in the letters of 'heated rows in essex'.
'resulting from' is the link.
(Other definitions for drowsiness that I've seen before include "Dozy feeling" , "Lethargy, somnolence" .)