lightship n : a ship equipped like a lighthouse and anchored where a permanent lighthouse would be impracticable
Lightship can mean:
- Lightvessel - For permanently moored ships that have light beacons mounted on them, see Lightvessel
- Lightship condition - in which a vessel has the least draft possible. The scenario is usually taken to be an unloaded vessel during the winter months in the northern hemisphere. During the winter months in the northern hemisphere, the water is colder and denser. This supports the ship more, causing it to have a shallower draft.