Angry son leaving Mansfield in a rage (8)
I believe the answer is:
inflamed
'angry' is the definition.
(I've seen this before)
'son leaving mansfield in a rage' is the wordplay.
'son' becomes 's' (genealogical abbreviation for son).
'leaving' suggests deleting specific letters.
'in a rage' indicates an anagram (disturbed or raging version of the letters).
'mansfield' with 's' removed is 'manfield'.
'manfield' with letters rearranged gives 'INFLAMED'.
(Other definitions for inflamed that I've seen before include "Swollen, hot, red" , "Red and sore" , "Angry" , "Provoked (someone) to strong feelings" , "one so hot and bothered" .)