shellflower

== English == === Etymology === From shell +‎ flower. === Noun === shellflower (plural shellflowers) A floating aquatic plant, of species Pistia stratiotes, with green rosettes of leaves and inconspicuous flowers. Synonyms: water lettuce, water cabbage Moluccella laevis, a plant in the mint family grown for its distinctive circular green calyxes. Synonyms: bells of Ireland, Molucca balm