Malpractice on a coach to the capital of Egypt (5)
I believe the answer is:
abuse
'malpractice' is the definition.
(thesaurus)
'a coach to the capital of egypt' is the wordplay.
'coach' becomes 'bus' (synonyms).
'to the capital of' suggests taking the first letters.
The initial letter of 'egypt' is 'e'.
'a'+'bus'+'e'='ABUSE'
'on' is the link.
(Other definitions for abuse that I've seen before include "Vilify" , "Party official; dessert" , "Cruel treatment" , "Maltreat" , "Vituperation" .)