Partly determining final points (7)
I believe the answer is:
termini
'points' is the definition.
(terminus is a kind of point)
'partly determining final' is the wordplay.
'partly' indicates the answer is hidden within the clue (part of the clue is used).
'TERMINI' can be found hidden inside 'determining final'.
(Other definitions for termini that I've seen before include "Railway ends" , "End points of rail or bus routes" , "Finishing points" , "Some like Victoria" , "End-points" .)