Noah Webster's Dictionary 1. (n.) Same as Bowlder. 2. (n.) A large stone, worn smooth or rounded by the action of water; a large pebble. 3. (n.) A mass of any rock, whether rounded or not, that has been transported by natural agencies from its native bed. See Drift.

Multi-Version Concordance Boulder (1 Occurrence) Revelation 18:21 A mighty angel took up a stone like a great millstone and cast it into the sea, saying, "Thus with violence will Babylon, the great city, be thrown down, and will be found no more at all. (See NIV)