|Easton's Bible Dictionary|
Genesis 11:3, R.V., margin, rendered in the A.V. "slime"), a mineral pitch. With this the ark was pitched (6:14. See also Exodus 2:3.) (see SLIME.)
Noah Webster's Dictionary
1. (n.) 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.
2. (n.) By extension, any one of the natural hydrocarbons, including the hard, solid, brittle varieties called asphalt, the semisolid maltha and mineral tars, the oily petroleums, and even the light, volatile naphthas.
Int. Standard Bible Encyclopedia
Bitumen (3 Occurrences)
Genesis 11:3 and they say each one to his neighbour, 'Give help, let us make bricks, and burn 'them' thoroughly:' and the brick is to them for stone, and the bitumen hath been to them for mortar. (YLT RSV)
Genesis 14:10 And the valley of Siddim 'is' full of bitumen-pits; and the kings of Sodom and Gomorrah flee, and fall there, and those left have fled to the mountain. (YLT RSV)
Exodus 2:3 and she hath not been able any more to hide him, and she taketh for him an ark of rushes, and daubeth it with bitumen and with pitch, and putteth the lad in it, and putteth 'it' in the weeds by the edge of the River; (YLT RSV)