[1] : The Collaborative International Dictionary of English v.0.48

zostera \zos"tera\, n. nl. bot.
   a genus of plants of the naiadaceae, or pondweed family.
   zostera marina is commonly known as sea wrack, and
   eelgrass.
   1913 webster
see also:
naiadaceae zostera marina sea wrack eelgrass 

[2] : WordNet (r) 2.0

zostera
     n : or in some classifications family zosteraceae small genus
         of widely distributed marine plants syn: genus zostera
see also:
genus zostera 

Zostera >> Z Words
Zostera, definition of term: Zostera
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