[kar-uh-geen] 
| Irish moss. |
| a purplish-brown, cartilaginous seaweed, Chondrus crispus, of the Atlantic coasts of Europe and North America. |
| car·ra·geen also car·ra·gheen (kār'ə-gēn') n. See Irish moss. [After Carragheen, a village of southeast Ireland.] |
| Irish moss n. An edible North Atlantic seaweed (Chondrus crispus) that yields a mucilaginous substance used medicinally and in preparing jellies. Also called carrageen. |
carrageen
(Chondrus crispus), species of red tufted seaweed with thin fronds from 5 to 25 cm (2 to 10 inches) long that grows abundantly along the rocky parts of the Atlantic coast of the British Isles, continental Europe, and North America. The plant is cartilaginous, varying in colour from a greenish yellow to a dark purple; when sun-dried and bleached it has a yellowish, translucent, hornlike aspect and consistency. The principal constituent of Irish moss is a gelatinous substance, carrageenan, which can be extracted by boiling. Carrageenan is used for curing leather and as an emulsifying and suspending agent in pharmaceuticals, food products, cosmetics, and shoe polishes. In North America it is harvested from shallow water by dredging with special rakes; in Europe it is usually obtained from plants cast ashore.
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