In a high degree supporting quality food shop distribution (8)
I believe the answer is:
delivery
'distribution' is the definition.
(thesaurus)
'in a high degree supporting quality food shop' is the wordplay.
'in a high degree' becomes 'very' (I've seen this before).
'supporting' is a charade indicator (letters next to each other) (in a down clue, some letters go below others).
'quality food shop' becomes 'deli' (I can't justify this - if you can you should believe this answer much more).
'very' put after 'deli' is 'DELIVERY'.
Can you help me to learn more?
(Other definitions for delivery that I've seen before include "Carriage and supply" , "Manner of making speech or bowling a ball" , "Address" , "Consignment" , "articulation" .)