Cut round page in part (5)
I believe the answer is:
split
'part' is the definition.
(splitting is a kind of parting)
'cut round page' is the wordplay.
'cut' becomes 'slit' (slitting is a kind of cutting**).
'round' means one lot of letters goes inside another.
'page' becomes 'p'.
'slit' going around 'p' is 'SPLIT'.
'in' is the link.
(Other definitions for split that I've seen before include "See 18" , "Riven; schism" , "ice cream concoction" , "Cause fission of (atom)" , "Cleave or divide" .)