Practise about funeral vehicle (8)
I believe the answer is:
rehearse
'practise' is the definition.
(I know that practise can be written as rehearse)
'about funeral vehicle' is the wordplay.
'about' becomes 're' (regarding).
'funeral vehicle' becomes 'hearse' (vehicle used in a funeral).
're'+'hearse'='REHEARSE'
(Other definitions for rehearse that I've seen before include "Go over" , "prepare for performance" , "Prepare for a stage production" , "Practise - run through" , "Train" .)