Senior citizen upset Mary about nothing (5)
I believe the answer is:
mayor
'senior citizen' is the definition.
The answer and definition can be both people as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'upset mary about nothing' is the wordplay.
'upset' is an anagram indicator.
'about' means one lot of letters goes inside another.
'nothing' becomes 'O' (looks like zero - 0).
'mary' is an anagram of 'mayr'.
'mayr' going around 'o' is 'MAYOR'.
Can you help me to learn more?
(Other definitions for mayor that I've seen before include "Civic leader" , "City government head" , "Officer" , "Town's elected head" , "Town official" .)