The Collaborative International Dictionary of English v.0.48:

Timpano \Tim"pa*no\, n.; pl. Timpani. [It.] (Mus.)
   See Tympano.
   [1913 Webster] Timur

WordNet (r) 3.0 (2006):

timpani
    n 1: a large hemispherical brass or copper percussion instrument
         with a drumhead that can be tuned by adjusting the tension
         on it [syn: kettle, kettledrum, tympanum, tympani,
         timpani]