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 carrying only ballast.
Bal"last, v. t. [imp. & p. p. Ballasted; p. pr. & vb. n. Ballasting.] 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.