Michael nurses a very stunted stray animal (8)
I believe the answer is:
maverick
'animal' is the definition.
(maverick is a kind of animal)
'michael nurses a very stunted stray' is the wordplay.
'michael' becomes 'mick' ().
'nurses' means one lot of letters goes inside another (nurse can mean to hold onto or harbour).
'a very' becomes 'av' (I've seen this in other clues).
'stunted' means to remove the last letter (the word is shorter than it usually is).
'stray' becomes 'err' ('err' can be a synonym of 'stray').
'err' with its final letter removed is 'er'.
'av'+'er'='aver'
'mick' placed around 'aver' is 'MAVERICK'.
(Other definitions for maverick that I've seen before include "Determined individualist" , "Renegade" , "Unconventional person or unbranded calf in America" , "Unorthodox type" , "Unorthodox or independent-minded person" .)