n. 1. A cap which fits the head closely; also, formerly, a headpiece of iron sewed inside of a cap for protection. [ 1913 Webster ]
2. (Bot.) Any plant of the labiate genus Scutellaria, the calyx of whose flower appears, when inverted, like a helmet with the visor raised. [ 1913 Webster ]
3. (Zool.) The Lophiomys. [ 1913 Webster ]
Mad-dog skullcap (Bot.), an American herb (Scetellaria lateriflora) formerly prescribed as a cure for hydrophobia. [ 1913 Webster ]