Odd parts declined by John Wayne? He pulled out at the last minute (4)
I believe the answer is:
onan
'odd parts declined by john wayne? he pulled' is the definition.
I know nothing about this answer so I cannot judge whether this works.
'out at the last minute' is the wordplay.
'out' is an insertion indicator.
'at' becomes 'on' (location).
'the last minute' becomes 'na' (I can't justify this - if you can you should give a lot more credence to this answer).
'on' enclosing 'na' is 'ONAN'.
Can you help me to learn more?
(Another definition for onan that I've seen is " Judah's second son".)