Deny daughter is parking over convertible (8)
I believe the answer is:
disprove
'deny' is the definition.
(thesaurus)
'daughter is parking over convertible' is the wordplay.
'daughter' becomes 'd' (genealogical abbreviation).
'parking' becomes 'p' (abbreviation on road signs).
'convertible' indicates anagramming the letters.
'over' with letters rearranged gives 'rove'.
'd'+'is'+'p'+'rove'='DISPROVE'
(Other definitions for disprove that I've seen before include "Refute, rebut" , "Negate" , "Demonstrate to be false" , "challenge successfully?" , "Show to be false - so provide" .)