(1):

(n.) Impure soda obtained from the ashes of any seashore plant, or kelp.

(2):

(n.) The alkali produced from the plant, being an impure carbonate of soda, used for making soap, glass, etc., and for bleaching purposes.

(3):

(n.) A name given to several species of Salsola from which soda is made, by burning the barilla in heaps and lixiviating the ashes.