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1. A division of an ocean or a large body of salt water partially enclosed by land
    
2. Anything apparently limitless in quantity or volume
   - ocean
    
3. Turbulent water with swells of considerable size
   "heavy seas"

Sounds like: see, C

Derived forms: seas

See also: marine, pelagic, thalassic

Type of: body of water, large indefinite amount, large indefinite quantity, turbulent flow, water

Part of: hydrosphere

Encyclopedia: Sea Sea, Lake, and Overland Surge from Hurricanes