What the fishwife may have on hand? (7)
I believe the answer is:
herring
'hand?' is the definition.
Although both the answer and definition are singular nouns, I can't understand how one could define the other.
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for herring that I've seen before include "Important food fish" , "one could be soused" , "Saltwater fish" , "Fish of northern waters, can be salted or pickled" , "Sprat" .)