the food supplied to the israelites in their journey through the wilderness of arabia; hence, divinely supplied food.-a name given to lichens of the genus lecanora, sometimes blown into heaps in the deserts of arabia and africa, and gathered and used as food.-a sweetish exudation in the form of pale yellow friable flakes, coming from several trees and shrubs and used in medicine as a gentle laxative, as the secretion of fraxinus ornus, and f. rotundifolia, the manna ashes of southern europe.