» For other uses, see: meniscus (anatomy) and lens (optics). Meniscus, plural: menisci/meniscuses, from the Greek for "crescent",'s a curve in the surface of a molecular substance and's produced in response to the surface of the container or another object. It can be either concave or convex. A convex meniscus occurs when the molecules have a stronger attraction to each other than to the container. This may be seen between mercury and glass in barometers. Conversely, a concave meniscus occurs w… (More on Meniscus)