n. A timber or steel bar extending from the keel to the main deck at the stern of a vessel.
the GNU version of the Collaborative International Dictionary of English
n. A straight piece of timber, or an iron bar or beam, erected on the extremity of the keel to support the rudder, and receive the ends of the planks or plates of the vessel.
The Century Dictionary and Cyclopedia
n. The principal piece of timber or iron in a vessel's stern-frame.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. (nautical) the principal upright timber at the stern of a vessel
Word Usage
"We had to replace a couple of planks under the water, the sternpost and most of the intermediate frames, says Mr. Barker, adding that fortunately much of the hull and hatches were salvageable."