Apron - The forward part of the stage between the curtain and the orchestra pit

Aria - A song for solo voice with instrumental accompaniment. Arias appear in cantatas, oratorios, and operas beginning in the 17trh century. Usually they emphasize musical expression more than the text. The text is often reflective, rather than descriptive of action. Arias are usually not strophic and they provide lyric interludes that temporarily pull the listener away from the action of the story.

Ballad Opera - A form of 18th century English operatic entertainment that consisted of spoken dialogue and musical numbers from popular music sources such as ballads, folk songs, and songs from other plays. The first example was The Beggar's Opera (1728) by John Gay, with music arranged by J. Pepusch. It was a satire of the Italian opera seria popular in London at the time.

Baritone - A male voice with a range between that of the low bass voice and the high tenor. The usual span is between G and E. Baritone parts may require either expressive, lyrical singing or they may be more heroic, as in the title role of Verdi's Rigoletto.

Baroque - The period in music history that spans from approximately 1600 to 1750. This period saw the birth of opera through the efforts of the Florentine Camerata and the works of Monteverdi. The best known late baroque operas are those of G.F. Handel.

Bass - The lowest male voice, frequently subdivided in several categories (see following entries). The range is between E and C'. This example is Mussorgsky's Boris Godunov.

Basso Buffo - A category of bass voice that specializes in comic roles, frequently seen in the operas of Mozart and Rossini. Dr. Bartolo in Rossini's The Barber of Seville is a famous example.

Basso Cantante - A type of bass voice that demonstrates a melodic, singing quality rather than a comic or tragic one. An example is King Philip in Verdi's Don Carlos.

Basso Profundo - The most serious of the bass voices. Sarastro in Mozart's The Magic Flute is an example.

Bel Canto - "Beautiful song," the traditional art of Italian singing which emphasizes elegant phrasing, beautiful tone and brilliant technique; bel canto flourished in the early to mid-19th century, in the works of Rossini, Bellini and Donizetti.

Blocking - The moving of people around the stage by the stage director to set up the patterns that will be followed during the performance of the opera