| Term | Definition |
|---|---|
| arch | A curved architectural structure used to support suspended weight. In Great Lakes wooden shipbuilding, a wide iron- or steel-fastened strap down each side of a ship, usually fastened low in the bow and stern and rising to the level of the upper deck amidships; provides longitudinal support to the hull. |
| arch board | An arch-shaped nameboard fastened to the stern of a ship, displaying the vessel's name and home port. |