Characteristic of vehicles with tail end low (9)
I believe the answer is:
wheelbase
'characteristic of vehicles' is the definition.
The definition and answer can be both human attributes as well as being singular nouns.
Perhaps you can see a link between them that I don't see?
'with tail end low' is the wordplay.
'with' becomes 'w' (abbreviation).
'tail end' becomes 'heel' (heel can mean the end of something. I am not sure about the 'tail' bit.).
'low' becomes 'base' (synonyms).
'w'+'heel'+'base'='WHEELBASE'
Can you help me to learn more?
(Other definitions for wheelbase that I've seen before include "Length of most of car" , "Source of power" .)