Bitumen \Bi*tu"men\, n. [L. bitumen: cf. F. bitume. Cf. B['e]ton.]

1. Mineral pitch; a black, tarry substance, burning with a bright flame; Jew's pitch. It occurs as an abundant natural product in many places, as on the shores of the Dead and Caspian Seas. It is used in cements, in the construction of pavements, etc. See Asphalt.

Source: Webster's Revised Unabridged Dictionary (1913)