Narrow natural waterway (6)
I believe the answer is:
strait
(Other definitions for strait that I've seen before include "Inlet" , "Narrow stretch of sea" , "Narrow stretch of water for artist" , "Sound" , "Narrow sea passage" .)
I believe the answer is:
strait
(Other definitions for strait that I've seen before include "Inlet" , "Narrow stretch of sea" , "Narrow stretch of water for artist" , "Sound" , "Narrow sea passage" .)