tym·pa·num /ˈtɪmpənəm/ 名詞
Tym·pa·num n.; pl. E. Tympanums L. Tympana
1. Anat. (a) The ear drum, or middle ear. Sometimes applied incorrectly to the tympanic membrane. See Ear. (b) A chamber in the anterior part of the syrinx of birds.
2. Zool. One of the naked, inflatable air sacs on the neck of the prairie chicken and other species of grouse.
3. Arch. (a) The recessed face of a pediment within the frame made by the upper and lower cornices, being usually a triangular space or table. (b) The space within an arch, and above a lintel or a subordinate arch, spanning the opening below the arch.
4. Mech. 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.
n 1: the main cavity of the ear; between the eardrum and the
inner ear [syn: middle ear, tympanic cavity]
2: the membrane in the ear that vibrates to sound [syn: eardrum,
tympanic membrane, myringa]
3: a large hemispherical brass or copper percussion instrument
with a drumhead that can be tuned by adjusting the tension
on it [syn: kettle, kettledrum, tympani, timpani]
[also: tympana (pl)]