open water

open water (usually uncountable, plural open waters)

1. An expanse of an ocean, sea, or large lake which is distant from shore and devoid of nearby islands or other obstructions.
   • 1851 November 14, Herman Melville, chapter 13, in Moby-Dick; or, The Whale, 1st American edition, New York, N.Y.: Harper & Brothers; London: Richard Bentley, →OCLC:

     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.

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.
   • 1916, Joseph A. Altsheler, chapter 1, in The Hunters of the Hills:

     Willet sent the canoe through the open water between the tall reeds.

3. (chiefly Canada) An area of an ocean, sea, lake, or river which is not covered by ice.
   • 2005, "Seasonal Summary for the Canadian Arctic, Summer 2005," Canadian Ice Service, Government of Canada, 6 Dec, p. 1 (retrieved 14 Mar. 2008):

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

• open sea