Tym"pa*num (?), n.; pl. E.
Tympanums (#), L. Tympana (#). [L., a
kettledrum, a drum or wheel in machines, the triangular area in a pediment,
the panel of a door, Gr. &?;, &?;, fr. &?; to strike, beat. See
Type, and cf. Timbrel.] 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. (Zoöl.) 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.
Tym"pa*num (?), n.; pl. E.
Tympanums (#), L. Tympana (#). [L., a
kettledrum, a drum or wheel in machines, the triangular area in a pediment,
the panel of a door, Gr. &?;, &?;, fr. &?; to strike, beat. See
Type, and cf. Timbrel.] 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. (Zoöl.) 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.
