n. Any cap fitting closely to the head; also, the iron cap of defense. See skull, 4.n. The sinciput; the upper domed part of the skull, roofing over the brain; the calvarium. See cut under cranium.n. A murine rodent quadruped of the family Lophiomyidæ.n. A plant of the genus Scutellaria: so called from the helmet-like appendage to the upper lip of the calyx, which closes the mouth of the calyx after the fall of the corolla.n. A thin stratum of compact limestone lying at the base of the Purbeck beds, and underlain by a shelly limestone locally known as roach, forming the uppermost division of the Portland series, as this portion of the Jurassic is developed in the so-called Isle of Portland, England.n. In entomology, the upper part of the integument of the head, including the front and vertex.