Wine/Port in Germany? Yes (5)
I believe the answer is:
rioja
'yes' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for rioja that I've seen before include "Popular Spanish wine" , "Spanish wine variety" , "Spanish red wine" , "kind of red" , "Spanish wine type" .)