Reference
Description and usage
The keel was the bottom, center structural part of a boat or ship. It usually extended somewhat below the bottom of the vessel in order to add to its stability.
Translation
Even where ships and boats are known, the average reader may not be familiar with specific parts of such a vessel. Therefore it may be best to avoid the technical term in WIS 5:10. For the more literal “when it has passed no trace can be found, nor track of its keel in the waves” (RSV), GNT has “when it is gone, it leaves no trace. You cannot tell it was ever there.”