Definition of sea grass
1a : a tassel grass (Ruppia maritima) b : a plant of the genus Salicornia (especially S. europaea) c : thrift 6 d or sea hay : eelgrass 1; also : its dried stems widely used for stuffing furniture and in making coarse fabrics
2 : any of several seaweeds; especially : a green alga (genus Enteromorpha) that often causes fouling of the bottoms of ships
3 : a cirrus cloud of wavy hairlike elements
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First Known Use of sea grass
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