n. a projection or ridge that suggests a keel
n. the median ridge on the breastbone of birds that fly
n. one of the main longitudinal beams (or plates) of the hull of a vessel; can extend vertically into the water to provide lateral stability
n. 龙骨, 平底船
vt. 装以龙骨, 使倾覆
vi. 倾覆
1. The ship's keel keeps it stable in the water.
船的龙骨使它在水中保持稳定。
2. They measured the length of the keel to ensure it was strong enough.
他们测量了龙骨的长度，以确保它足够坚固。
3. The keel is an important part of a boat's structure.
龙骨是船只结构中一个重要的部分。