Found 2 items, similar to marl.
English → English (WordNet) Definition: marl marl n : a loose and crumbling earthy deposit consisting mainly of calcite or dolomite; used as a fertilizer for soils deficient in lime
English → English (gcide) Definition: marl Greensand \Green"sand`\ (-s[a^]nd`), n. (Geol.) A variety of sandstone, usually imperfectly consolidated, consisting largely of glauconite, a silicate of iron and potash of a green color, mixed with sand and a trace of phosphate of lime. [1913 Webster] Note: [hand]Greensand is often called marl, because it is a useful fertilizer. The greensand beds of the American Cretaceous belong mostly to the Upper Cretaceous. [1913 Webster]