Glen and Iris spilled white wine (8)
I believe the answer is:
riesling
'white wine' is the definition.
(Riesling is an example)
'glen and iris spilled' is the wordplay.
'and' says to put letters next to each other.
'spilled' indicates an anagram.
'glen' put after 'iris' is 'irisglen'.
'irisglen' is an anagram of 'RIESLING'.
(Other definitions for riesling that I've seen before include "Strange wine for Sir Ingle" , "Fragrant white wine from the Rhine valley or from California" , "Sir Ingle makes wine from this grape" , "Aromatic white wine from the Rhine valley" , "German/Austrian wine" .)