Starter opposing late beginning of Oaks (9)

I believe the answer is:

antipasto

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'starter' is the definition.
(I've seen this before)

'opposing late beginning of oaks' is the wordplay.
'opposing' becomes 'anti'.
'late' becomes 'past' (I can't explain this - if you can you should believe this answer much more).
'beginning of' says to take the initial letters.
The first letter of 'oaks' is 'o'.
'anti'+'past'+'o'='ANTIPASTO'

Can you help me to learn more?

(Other definitions for antipasto that I've seen before include "dishes" , "Starter course in an Italian meal" , "Italian hors d'oeuvres" , "garnish!" , "course leader" .)

I've seen this clue in The Telegraph.

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