Opt against playing, leaving golf course (9)
I believe the answer is:
antipasto
'course' is the definition.
(antipasto is a kind of course)
'opt against playing leaving golf' is the wordplay.
I cannot really understand how this works, but
'against' could be 'anti' (prefix meaning against) and 'anti' is present in the answer.
'playing' could be 'as' (I've seen this in other clues) and 'as' is found in the answer.
an anagram of 'opt' is 'pto' which is within the left over letters.
No letters remain.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for antipasto that I've seen before include "Appetizer course in an Italian meal" , "garnish!" , "dishes" , "Italian hors d'oeuvre" , "Appetiser, starter" .)