Stubborn person put on small island (6)
I believe the answer is:
donkey
'stubborn person' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how they can define each other.
'put on small island' is the wordplay.
'put on' becomes 'don' (as in donning or putting on an item of clothing).
'small island' becomes 'key' (I've seen this before).
'don'+'key'='DONKEY'
Can you help me to learn more?
(Other definitions for donkey that I've seen before include "Braying quadruped" , "Domesticated ass" , "Beasts of burden" , "stubborn type" , "Ass; stupid person" .)