Wine stain unfortunately showing up (7)
I believe the answer is:
marsala
'wine' is the definition.
(Marsala is an example)
'stain unfortunately showing up' is the wordplay.
'stain' becomes 'mar'.
'unfortunately' becomes 'alas' (I've seen this before).
'showing up' is a reversal indicator.
'alas' backwards is 'sala'.
'mar'+'sala'='MARSALA'
(Other definitions for marsala that I've seen before include "Dessert wine from Sicily" , "Sweet Sicilian wine" , "Sweet dessert wine" , "Alcoholic drink" , "Sicilian dessert wine" .)