1. Nautical. The distance between the water line and the freeboard deck of a ship.
2. The distance between normal water level and the top of a structure, such as a dam, that impounds or restrains water.
3. The distance between the ground and the undercarriage of an automobile.

[Probably ultimately partial translation of Anglo-Norman franc bord, land claimed outside the fence of a park or forest : franc, free + bord, bort, border; see border.]

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.