Ossia is a musical term for an alternative passage which may be played instead of the original passage. The word ossia comes from the Italian

Italian language

Italian is a Romance language spoken mainly in Europe: Italy, Switzerland, San Marino, Vatican City, by minorities in Malta, Monaco, Croatia, Slovenia, France, Libya, Eritrea, and Somalia, and by immigrant communities in the Americas and Australia...

 for "alternatively" and was originally spelled o sia, meaning "or be it" (Fallows 774). Ossias are very common in opera

Opera

Opera is an art form in which singers and musicians perform a dramatic work combining text and musical score, usually in a theatrical setting. Opera incorporates many of the elements of spoken theatre, such as acting, scenery, and costumes and sometimes includes dance...

 and solo piano

Piano

The piano is a musical instrument played by means of a keyboard. It is one of the most popular instruments in the world. Widely used in classical and jazz music for solo performances, ensemble use, chamber music and accompaniment, the piano is also very popular as an aid to composing and rehearsal...

 works. In practice, ossia passages usually are an easier version of the preferred form of passage, but in Mily Balakirev

Mily Balakirev

Mily Alexeyevich Balakirev ,Russia was still using old style dates in the 19th century, and information sources used in the article sometimes report dates as old style rather than new style. Dates in the article are taken verbatim from the source and therefore are in the same style as the source...

's Islamey: an Oriental Fantasy

Islamey: an Oriental Fantasy

Islamey , Op. 18, is a composition for piano by Russian composer Mily Balakirev, written in September 1869....

, for instance, the urtext

Urtext

Urtext is a word of German origin; ur- means "original," and text is as in English.In the humanities and social sciences, the word is often used in a metaphorical fashion to refer to a primitive, seminal, or prototypical example of an artistic genre or the basis of an ideological movement...

 has ossia passages of both types (simpler and more difficult). Bel canto

Bel canto

Bel canto , along with a number of similar constructions , is an Italian opera term...

 vocal music also frequently uses ossias to illustrate a more embellished version of the vocal line (Fallows 774). On the other hand, an Ossia marking does not always indicate a change in difficulty; the piano solo music of Franz Liszt

Franz Liszt

Franz Liszt ; ), was a 19th-century Hungarian composer, pianist, conductor, and teacher.Liszt became renowned in Europe during the nineteenth century for his virtuosic skill as a pianist. He was said by his contemporaries to have been the most technically advanced pianist of his age...

 is typically full of alternative passages, often no easier or more difficult than the rest of the piece. This reflects Liszt's desire to leave his options open during a performance. Many of his Ossia passages are cadenza

Cadenza

In music, a cadenza is, generically, an improvised or written-out ornamental passage played or sung by a soloist or soloists, usually in a "free" rhythmic style, and often allowing for virtuosic display....

s.

An unusual use of ossia is found in the Berg Violin Concerto

Violin Concerto (Berg)

Alban Berg's Violin Concerto was written in 1935 . It is probably Berg's best-known and most frequently performed instrumental piece.-Conception and composition:...

 where several ossia parts are included for the solo violin. If the soloist chooses to play these ossias, the concert master is required to play different ossias (which take part of the solo violin line that is lost in favor of the soloist's ossias).