Definition of "tympanum"

(archaic) A drum.

(anatomy, zootomy) Any of various anatomic structures in various animals with analogy to a drum head:

1. (anatomy, zootomy) The eardrum (tympanic membrane, membrana tympanica).  examples

2. (anatomy, zootomy) The main portion of the middle ear: the tympanic cavity (cavitas tympani).  examples

3. (zootomy, entomology) A thin tense membrane covering the hearing organ on the leg or body of some insects, sometimes adapted (as in cicadas) for producing sound.

4. (zootomy) A membranous resonator in a sound-producing organ in frogs and toads.  examples

5. (zootomy) (in certain birds) The labyrinth at the bottom of the windpipe.  examples

(architecture) A vertical recessed triangular space between the sides of a pediment, typically decorated

1. The recessed triangular space within an arch, and above a lintel or a subordinate arch, spanning the opening below the arch  quotations  examples

   Quotations

   • It was a black-and-white picture of a Romanesque doorway, with flanking saints and a lively Last Judgement in the tympanum […] .

     2004, Alan Hollinghurst, The Line of Beauty […], 1st US edition, New York, N.Y.: Bloomsbury Publishing

(engineering) 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.  examples