Also found in: Dictionary, Wikipedia.
Related to Vitrain: durain
one of the components of coal. Its chemical properties are similar to those of the humus substances in peat. The vitrain in coal contains more carbon and has less H, O, and volatile substances in proportion to the degree of transition from the brown coals to anthracite. Vitrain exists in a form of lenses or layers of various thicknesses and is the least cinderlike component of coal.