Spin out part in next Endeavour (6)
I believe the answer is:
extend
'spin out' is the definition.
(I've seen this before)
'part in next endeavour' is the wordplay.
'part in' indicates a hidden word.
'EXTEND' can be found hidden inside 'next endeavour'.
(Other definitions for extend that I've seen before include "Provide challenge" , "Reach out, say the hand of friendship" , "continue" , "Draw out" , "Carry on" .)