Comedian I overlooked is appearing on a list (4)
I believe the answer is:
rota
'list' is the definition.
(rota is a kind of list)
'comedian i overlooked is appearing on a' is the wordplay.
'comedian' becomes 'riot' (both can mean an amusing person).
'overlooked' is a deletion indicator.
'is appearing on' means one lot of letters go next to another.
'riot' with 'i' taken out is 'rot'.
'rot'+'a'='ROTA'
(Other definitions for rota that I've seen before include "Work roster" , "Ecclesiastical tribunal" , "Duty schedule" , "supreme Catholic court" , "Duty roster" .)