Aria
An aria was a song given by one or two performers in an opera.

In 2373, The Doctor sang the aria O, soave fanciulla from the opera La bohème by Giacomo Puccini. ()

When B'Elanna Torres experienced a vision of the Klingon afterlife in 2376, The Doctor claimed he'd perform an aria from The Damnation of Faust by Louis Hector Berlioz. ()

Also that year, Mareeza composed an aria based on the Sky Ship; The Doctor sang the lyric. ()

In 2377, The Doctor hummed an aria from Rigoletto, which made Fantome relax, so The Doctor subsequently played the full orchestral version. ()

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Earth music genres