Mĕs'o-lābe, n.

n. [Fr. mésolabe, Lat. mesolabium, Gr. μεσολάβος, from μέσος, middle, and λαμβάνειν, to take.] An instrument employed by the ancients for finding two mean proportionals between two given lines, which were required in the problem of the duplication of the cube. Brande.