The Detroit River flows into it (4)
I believe the answer is:
erie
'the detroit river flows into it' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for erie that I've seen before include "A Great American lake - sounds spooky" , "Great lake in Eire" , "The lake sounds weird" , "Buffalo's lake" , "Lake between Canada and the US" .)