roche

(Chem.) A kind of alum occuring in small fragments; -- so called from Rocca, in Syria, whence alum is said to have been obtained; -- also called rock alum. [ 1913 Webster ]

n. [ F. roche rock + E. lime. ] Lime in the lump after it is burned; quicklime. [ Eng. ] [ 1913 Webster ]

n. A seaport town in France. [ 1913 Webster ]

Rochelle powders. Same as Seidlitz powders. --
Rochelle salt (Chem.), the double tartrate of sodium and potassium, a white crystalline substance. It has a cooling, saline, slightly bitter taste and is employed as a mild purgative. It was discovered by Seignette, an apothecary of Rochelle, and is called also Seignete's salt. [ 1913 Webster ]

‖ [ F., sheep-shaped rock. ] (Geol.) See Sheepback. [ 1913 Webster ]

n. [ Probably corrupted fr. F. rouget the red gurnet, from rouge red. CF. Rouge. ] (Zool.) The red gurnard, or gurnet. See Gurnard. [ 1913 Webster ]