| Noun | 1. | genus Zostera - (or in some classifications family Zosteraceae) small genus of widely distributed marine plantsliliopsid genus, monocot genus - genus of flowering plants having a single cotyledon (embryonic leaf) in the seed family Potamogetonaceae, pondweed family, Potamogetonaceae - plants that grow in ponds and slow streams; sometimes includes family Zosteraceae eelgrass, grass wrack, sea wrack, Zostera marina - submerged marine plant with very long narrow leaves found in abundance along North Atlantic coasts |