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"imperfectly formed coal," 1808, from French, from Latin lignum "wood" (see ligni-). Brown coal that still shows traces of the wood it once was. Probably directly from Lithanthrax Lignius, name given to woody coal by Swedish chemist Johan Gottschalk Wallerius (1709-1785) in 1775.
A soft, brownish-black form of coal having more carbon than peat but less carbon than bituminous coal. Lignite is easy to mine but does not burn as well as other forms of coal. It is a greater polluter than bituminous coal because it has a higher sulphur content. Compare anthracite, bituminous coal.