Protocol over occupying uniform part of track for racing (7,3)
I believe the answer is:
formula one
'racing' is the definition.
(motor racing)
'protocol over occupying uniform part of track' is the wordplay.
'protocol' becomes 'form' (form can mean protocol or procedure).
'over' becomes 'o' (cricket abbreviation).
'occupying' means one lot of letters goes inside another.
'uniform' becomes 'U' (phonetic alphabet: alpha, bravo, charlie etc.).
'part of track' becomes 'lane'.
'u'+'lane'='ulane'
'o' put into 'ulane' is 'ulaone'.
'form'+'ulaone'='FORMULA ONE'
'for' is the link.
(Other definitions for formula one that I've seen before include "Auto racing class" , "sort of GP" .)