Put off on top and sped off (9)
I believe the answer is:
postponed
'put off' is the definition.
(I've seen this before)
'on top and sped off' is the wordplay.
'and' says to put letters next to each other (I've seen this in other clues).
'off' indicates an anagram.
'on'+'top'='ontop'
'ontop' put after 'sped' is 'spedontop'.
'spedontop' anagrammed gives 'POSTPONED'.
(Other definitions for postponed that I've seen before include "delayed" , "Deferred" , "Put off" .)