Water that is not salty, for instance water found in lakes, streams, and
rivers, but not the ocean. Also used to refer to things living in or related to
freshwater (e.g., "freshwater fish").
Source: GreenFacts
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Freshwater is water that contains only minimal quantities of dissolved salts,
thus distinguishing it from sea water or brackish water.
All freshwater ultimately comes from precipitation of atmospheric water vapor,
reaching inland lakes, rivers, and groundwater bodies directly, or after melting
of snow or ice.