1. (Science: botany) The upper lip or helmet-shaped part of a labiate flower.
2. (Science: surgery) a kind of bandage for the head.
3. Headache extending all over the head.
4. (Science: paleontology) a genus of fossil echini, having a vaulted, helmet-shaped shell.
5. (Science: zoology) The anterior, outer process of the second joint of the maxillae in certain insects.
Origin: L, a helmet.