Twelfth Night cultural definition

A comedy by William Shakespeare. The two central characters are a twin brother and sister; each thinks that the other has been lost at sea. The sister disguises herself as a boy and goes to serve the duke of the country, a bitter man disappointed in love. The brother reappears and marries the woman whom the duke has been pursuing, and his sister marries the duke. Twelfth Night begins with the line “If music be the food of love, play on.”