Shallowest of the Great Lakes (4)
I believe the answer is:
erie
'shallowest of the great lakes' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for erie that I've seen before include "Buffalo's lake" , "N. American lake" , "Lake between Canada and the US" , "Great lake in Eire" , "Superior companion" .)