[UN-2 4. Cf. Du. ontballasten.]

1

  1.  Naut. To clear (a ship) of ballast. Also Unballasting vbl. sb.

2

a. 1684.  Leighton, Com. Pet. v. 6 (1849), II. 460. It is necessary time and pains that is given to the unballasting of a ship.

3

1769.  Falconer, Dict. Marine (1780), To unbalast, to discharge the ballast of a ship. [Hence in later dicts.] Ibid. (French Terms), [The] Maître de quai … is besides to appoint the proper places for ballasting and unballasting vessels.

4

  2.  fig. To render unsteady.

5

1836.  Blackw. Mag., XXXIX. 466. This pleasure … more completely unballasts the mind than any other.

6