One Barking prison given official documentation (5)
I believe the answer is:
canid
'one barking' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how they can define each other.
'prison given official documentation' is the wordplay.
'prison' becomes 'can' (the can is American slang for prison).
'given' says to put letters next to each other.
'official documentation' becomes 'id' (identification documents. I am not sure about the 'official' bit.).
'can'+'id'='CANID'
Can you help me to learn more?
(Another definition for canid that I've seen is " dog maybe".)