Definition of "sea-grass" [sea-grass]

• The thrift, Armeria vulgaris, and also one of the glassworts, Salicornia herbacea, both seaside plants; also, the eel-grass (Zostera marina), the tassel-grass(Rappia maritima), the gulfweed (Sargassum), and probably other marine plants. (noun)
• Variety of cirrus cloud whose form suggests the name: it is a forerunner of stormy weather. (noun)
• In phytogeography, a marine vegetation, or one of the plants composing it, which roots in loose soil under shallow water and sends up long floating leaves or stems; an enalid. Algæ (Caulerpa and Characeæ) are included under this term, phanerogams (Potamogetonaceæ and Vallisueriaceæ, including Enhalus) predominating. Compare benthos. (noun)

The Century Dictionary (Public Domain)

• "Her apartment is always clean and decorated perfectly, the sea-grass rug perfectly complementing her beige couch and navy chairs."
• "The marshlands, coral reefs, and sea-grass meadows that support coastal life are imperiled by ecological shocks such as major oil spills."
• "More water evaporates from the bay than flows into it from the Everglades this time of year, creating a sink-like effect that leaves the delicate ecosystem at some risk of attracting oil flows, said James Fourqurean, a sea-grass ecologist at Florida International University."