African runner's dad taken by car (7)
I believe the answer is:
limpopo
'african runner's' is the definition.
(African river, something which runs)
'dad taken by car' is the wordplay.
'dad' becomes 'pop' (synonyms).
'taken by' means one lot of letters goes inside another.
'car' becomes 'limo' (limo is a kind of car).
'pop' put within 'limo' is 'LIMPOPO'.
(Other definitions for limpopo that I've seen before include "River of SE Africa" , "S. Africa/Zimbabwe border river" , "River of South Africa" , "African river" , "African runner" .)