Extra large, large round cherry (7)
I believe the answer is:
morello
'cherry' is the definition.
(I know that morello is a type of sour cherry)
'extra large large round' is the wordplay.
'extra' becomes 'more' (both can mean additional).
'large large' becomes 'll' (this could be a standard abbreviation which I don't know about).
'round' becomes 'o' (round can mean a round object).
'more'+'ll'+'o'='MORELLO'
Can you help me to learn more?
(Other definitions for morello that I've seen before include "cherries" , "Cherry's" , "Small, dark, sour cherry" , "Dark-red variety of cherry" , "Sour red fruit" .)