Watch'-glass, n.
n. 1. A concavo-convex glass for covering the face or dial of a watch. 2. (Naut.) A half-hour glass, used to measure the time of a watch on deck.
n. 1. A concavo-convex glass for covering the face or dial of a watch. 2. (Naut.) A half-hour glass, used to measure the time of a watch on deck.