ballast

1. (Naut.) Any heavy substance, as stone, iron, etc., put into the hold to sink a vessel in the water to such a depth as to prevent capsizing. 2. Any heavy matter put into the car of a balloon to give it steadiness. 3. Gravel, broken stone, etc., laid in the bed of a railroad to make it firm and solid. 4. The larger solids, as broken stone or gravel, used in making concrete. 5. Fig.: That which gives, or helps to maintain, uprightness, steadiness, and security. It [piety] is the right ballast of prosperity. Barrow. Ballast engine, a steam engine used in excavating and for digging and raising stones and gravel for ballast. -- Ship in ballast, a ship carring only ballast. 1. To steady, as a vessel, by putting heavy substances in the hold. 2. To fill in, as the bed of a railroad, with gravel, stone, etc., in order to make it firm and solid. 3. To keep steady; to steady, morally. 'T is charity must ballast the heart. Hammond.

Source: Webster's Revised Unabridged Dictionary (1913), United States public domain. See methodology for full licensing detail. Word validity for game play may differ from any official game dictionary.