Manage a limo to develop narcissistic personality disorder (11)
I believe the answer is:
megalomania
'narcissistic personality disorder' is the definition.
The definition and answer can be both states of affairs as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'manage a limo to develop' is the wordplay.
'to develop' indicates an anagram.
'manage'+'a'+'limo'='managealimo'
'managealimo' anagrammed gives 'MEGALOMANIA'.
Can you help me to learn more?
(Other definitions for megalomania that I've seen before include "Delusion about one's own power" , "Illness" , "Passion for grandeur" , "Folie de grandeur" .)