Nonsense row about stray dog (4,7)
I believe the answer is:
bull terrier
'dog' is the definition.
(bull terrier is a kind of dog)
'nonsense row about stray' is the wordplay.
I cannot really understand how this works, but
'nonsense' could be 'bull' (I've seen this before) and 'bull' is located in the answer.
'stray' could be 'err' (to err is to stray or go wrong) and 'err' is located in the answer.
'row' could be 'tier' (a tier is a row of things) and 'tier' is found within the remaining letters.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Another definition for bull terrier that I've seen is " Breed of dog".)