a. [ L. bituminosus: cf. F. bitumineux. ] Having the qualities of bitumen; compounded with bitumen; containing bitumen. [ 1913 Webster ]

Near that bituminous lake where Sodom flamed. Milton. [ 1913 Webster ]

Bituminous coal, a kind of coal which yields, when heated, a considerable amount of volatile bituminous matter. It burns with a yellow smoky flame. --
Bituminous limestone, a mineral of a brown or black color, emitting an unpleasant smell when rubbed. That of Dalmatia is so charged with bitumen that it may be cut like soap. --
Bituminous shale, an argillaceous shale impregnated with bitumen, often accompanying coal. [ 1913 Webster ]