Girl seen in Oregon or Massachusetts (5)
I believe the answer is:
norma
'girl' is the definition.
'in oregon or massachusetts' is the wordplay.
'in' says the answer is hidden in the clue.
'NORMA' is hidden in the letters of 'oregon or massachusetts'.
'seen' is the link.
(Other definitions for norma that I've seen before include "John Major's wife - Bellini opera" , "Bellini heroine" , "Operatic work" , "Female" , "Manor (anag.)" .)