When I was studying Latin in college, I often encountered the word “opus.” This word means “work” in Latin. Later, when I studied music, I again encountered the shortened form of the opus. It was used after the title of a musical piece. So, it didn’t surprise me that “OP” would stand for a piece of music done by a composer.
Any great composer would have several musical compositions. Hence, his works must be organized and categorized. It is convenient to use the shortened form of opus to refer to his works. Beethoven, for example, wrote many piano sonatas. He also wrote several piano sonatas when he was young. He was so prolific as a musician that even in his old age, he was still penning piano sonatas.
Those who would look up his works will get confused without proper cataloging of his works. Good enough, there is the word “opus” to refer to his musical works easily. The number that follows the word opus refers to each specific work he had done in his musical career.
Beethoven’s Piano sonata, for example, in A flat major op 26, is his 26th piano sonata work. His opus no. 110 is another piano sonata he had written when he was old long after he had written the piano sonata opus no. 26.
What Does the Opus Number Indicate?
You may think that the opus number indicates the succession of works of a composer. But that is not always the case. It only tells us the order in which the work was published. Up to the 18th century, the opus number only referred to the order in which the piece was published.
At present, the opus number still refers to the chronological order of the publication of a particular work of a musical composer. Moreover, the opus number helps distinguish various musical compositions with the same title. The word “opus” is usually abbreviated as “Op” if it is referring to a single work. It is abbreviated as “Opp” when referring to a couple of works.
The Origin of the Word
Words have origins, and we call the study of the origin of words as the “etymology.” Hence, if you are asked about the etymology of the word “opus,” it is obvious that it comes from the Latin word “opus.” It means “work” or “labor.” In the classical period, “opus” referred to a work of art done by an artist. Thus, you would hear of the opus of Michelangelo and Leonardo da Vinci.
In music, “opus” was adapted in the 15th and 16th centuries to refer to the compositions of Italian composers. It also referred to the collections of music of German composers. Yet, the practice of naming musical composition using opus started in the 17th century in Venice. The best works of composers were often referred to as the “Magnus opus.”
There is a great relationship between the etymology of “opus” and “opera.” The word “opus” is a third declension noun that is declined as opus, operis, operi, opus, and opus. Its plural forms include opera, operum, operibus.
So, looking at how the word “opus” is declined in Latin, it is obvious that both opus and opera have the same origin. Hence, you will often encounter the word “opera” to refer to the works of a musical composer. Yet, the word “opera” had been closely associated with the dramatic musical genre of ballet and opera that evolved in Italy likewise.
OP and Its Usage
Op is commonly combined with a number to refer to the chronology of the works of a musical composer. So, you will see Op.1 or op.100, which refers to the chronological works of a composer. The plural form, of course, is “Opp to refer to a series of musical works of a composer.
In the English language, however, the plural form of “opus” is problematic. If you stick to Latin, the plural of this word will be “opera.” Yet, opera has a different connotation in English. Hence, many lexicographers make use of “opuses” as the plural form of “opus.”
Opus number, as mentioned earlier, however, does not refer to the order in which the composer made his work. It only refers to the order in which his works were published. So, if you would use it to trace the musical development of a composer, you may get confused. This is because a musical work might have been done a composer earlier, but he did not publish it immediately. Instead, he published his more recent works.
Modern Ways of Cataloging Musical Works
From Beethoven’s time onward, however, composers began to assign an opus number to their works before they send it to the publisher. But if you would use this to trace the succession of works of a composer, you would still find it problematic.
Hence, some diehard musicologists started to create their catalogs to chronologically catalog the order of the works of musical composers. They do this to manage the inconsistent of the opus-number usages. These musicologists made use of more unambiguous and more comprehensive catalog number systems for the works of great composers like Johann Sebastian Bach (BWV-number), Dietrich Buxtehude (BuxWV-number), and many more.