Ballet is a type of dance that originated from Earth. Performances are called ballets. Female dancers are called ballerinas, while male dancers were danseurs.
Kathryn Janeway was an accomplished ballerina; she took up ballet when she was six years old. (VOY: "Coda")
Pazzo was the only danseur in his Romulan Naval Academy class. He was accompanied by Lyran ballerinas. Some years later, Annika Hansen has fulfilled Seven of Nine's childhood dream by becoming the lead dancer of the Romulan Naval Academy (and later the Tal Prai'ex) in her stead. (RIS Bouteina)
Although the Simpsons considered Annika rather average, she did, on more than one occasion, give ballet lessons. (RIS Bouteina: "Miracle in Whoville")