Tympana meaning : A triangular space between the sides of a pediment. The space within an arch, and above a lintel or a subordinate arch, spanning the opening below the arch. The middle ear. The eardrum. A hearing organ in frogs, toads and some insects. In certain birds, the labyrinth at the bottom of the windpipe. A drum-shaped wheel with spirally curved partitions by which water is raised to the axis when the wheel revolves with the lower part of the circumference submerged; used for raising water, as for irrigation.