Vertigo

·noun Any one of numerous species of small land snails belonging to the genus Vertigo, having an elongated or conical spiral shell and usually teeth in the aperture.

II. Vertigo ·noun Dizziness or swimming of the head; an affection of the head in which objects, though stationary, appear to move in various directions, and the person affected finds it difficult to maintain an erect posture; giddiness.