Mum and dad upset after motorway accident (6)
I believe the answer is:
mishap
'accident' is the definition.
(mishap is a kind of accident)
'mum and dad upset after motorway' is the wordplay.
'mum' becomes 'sh' (I've seen this in other clues).
'and' says to put letters next to each other.
'dad upset' becomes 'ap' (I can't justify this - if you can you should give a lot more credence to this answer).
'after' says to put letters next to each other.
'motorway' becomes 'mi' (resembles Ma, English motorway).
'sh'+'ap' is 'shap'.
'shap' put after 'mi' is 'MISHAP'.
Can you help me to learn more?
(Other definitions for mishap that I've seen before include "Accident, unlucky happening" , "'Bad luck, mischance (6)'" , "Unpleasant accident" , "Contretemps" , "Blow" .)