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† tympănum, i (collat. form typă-num, Cat. 63, 8 sq.), n.,  =  τύμπανον, a drum, timbrel, tambour, tambourine. 
- I.  Lit. 
 
- A.  Esp., as beaten by the priests of Cybele, Lucr. 2, 618; Cat. 63, 8 sq.; Verg. A. 9, 619; Ov. M. 3, 537; 4, 29; 4, 391; id. F. 4, 213; Plaut. Poen. 5, 5, 38; Caes. B. C. 3,  105; Curt. 8, 11, 20; 8, 14, 10; Tac. H. 5, 5, 
Also by the Bacchantine females, Ov. M. 11, 17.
Beaten by the Parthians as a signal in battle in place of the tuba, Just. 41, 2, 8. 
- B.  Trop., a timbrel, etc., as a figure of something effeminate, enervating: tympana eloquentiae, Quint. 5, 12, 21: in manu tympanum est, Sen. Vit. Beat. 13, 3.
 
- II.  Transf., of things of a like shape. 
 
- A.  A drum or wheel, in machines for raising weights, in water-organs, etc., Lucr. 4, 905; Verg. G. 2, 444; Vitr. 10, 4; Plin. 18, 34, 77, § 332; Dig. 19, 2, 19.
 
- B.  In archit. 
 
- 1.  The triangular area of a pediment, Vitr. 3, 3 med.
 
- 2.  A panel of a door, Vitr. 4, 6 med.
 
- 3.  A part of the clepsydra, called also phellos, Vitr. 9, 9.