Dog may get the wrong end of the stick during row (7)
I believe the answer is:
terrier
'dog' is the definition.
(terrier is a kind of dog)
'get the wrong end of the stick during row' is the wordplay.
'get the wrong end of the stick' becomes 'err' (I can't explain this - if you can you should believe this answer much more).
'during' is an insertion indicator.
'row' becomes 'tier' (a tier is a row of things).
'err' placed into 'tier' is 'TERRIER'.
'may' acts as a link.
Can you help me to learn more?
(Other definitions for terrier that I've seen before include "Dog originally used to ferret out burrowing animals" , "Dog - reservist" , "Dog - old land register" , "Persistent person" , "Small, originally burrowing, dog" .)