open water

noun3

1. •
   An expanse of an ocean, sea, or large lake which is distant from shore and devoid of nearby islands or other obstructions.

   • Gaining the more open water, the bracing breeze waxed fresh; the little Moss tossed the quick foam from her bows, as a young colt his snortings. — 1851
2. •
   In a river, pond, or other small body of water, an area of surface unobstructed by aquatic vegetation, boulders, and the like, adequate for navigation or swimming.

   • Willet sent the canoe through the open water between the tall reeds. — 1916
3. •
   An area of an ocean, sea, lake, or river which is not covered by ice.

   • At the end of June, James Bay was generally open water except for loose ice persisting over its northwestern section. — 2005