Grom"well (?), n. [Called also gromel, grommel, graymill, and gray millet, all prob. fr. F. gr?mil, cf. W. cromandi.] (Bot.) A plant of the genus Lithospermum (L. arvense), anciently used, because of its stony pericarp, in the cure of gravel. The German gromwell is the Stellera. [Written also gromill.]