What does the musical term 'op' stand for?

Answer 1

Op. is short for opus, an Italian word that literally means "work." It is used to number the works of a given composer, usually in the order they are published, but sometimes, as with Beethoven for instance, it is in the order specified by the composer. Example, Beethoven's first published work, or opus, was a set of piano trios, so they are designated his Opus One, and each work within the opus is numbered. His first single work, then, is the Trio No. 1 in E-flat Major, Op. 1, No. 1. Some composers don't choose to use opus numbers. They are basically just a tool forcataloging.

Answer 2

Op. stands for "Opus number", to refer to a catalog of the composer's works (not just symphonies, but all compositions in general.)

Some composers whose works have been cataloged by particular specialists are more often referred to by special abbreviations for the catalog, e.g. Mozart's works are often numbered as "KWV ..." (Koechelwerkverzeichnis, since Koechel cataloged the works), Schubert's works "D. ..." for Otto Deutsch, and so on.

Answer 3

It stands for Opus, or "work".

It is used to catalogue a composer's works by number, usually in chronological order.