How feast begins with cut turkey (4)
I believe the answer is:
flop
'turkey' is the definition.
(I've seen this in another clue)
'how feast begins with cut' is the wordplay.
I cannot really understand how this works, but
'cut' could be 'lop' (lopping is a kind of cutting) and 'lop' is found within the answer.
A single letter 'f' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
(Other definitions for flop that I've seen before include "Theatrical failure" , "Failure - loll" , "Collapse loosely - total failure" , "Total failure; fall heavily" , "Fail" .)