The first person singular repeated in confusion (4)
I believe the answer is:
mess
'confusion' is the definition.
(thesaurus)
'the first person singular repeated' is the wordplay.
'the first person' becomes 'me' (first-person pronoun**).
'singular' becomes 's' (abbreviation sometimes used in dictionaries).
'repeated' shows that letters should be duplicated.
's' doubled is 'ss'.
'me'+'ss'='MESS'
'in' acts as a link.
(Other definitions for mess that I've seen before include "dog's dinner" , "Confused situation" , "Where officers eat" , "Army dining room" , "Dog's breakfast" .)