"Bates Motel” mother (5)
I believe the answer is:
norma
'bates motel mother' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for norma that I've seen before include "Marilyn was properly one" , "Marilyn Monroe's real first name" , "She incited Gauls v. Romans (Bellini)" , "Bellini work" , "Opera - ex-PM's wife" .)