"The Night Circus" novelist Morgenstern (4)
I believe the answer is:
erin
'the night circus novelist morgenstern' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for erin that I've seen before include "Land" , "(Literary name for) Ireland" , "Ireland (poet.)" , "country" , "Another name for 11 ac" .)