What Is the Oxford Comma and Why Is It Important?

It is common knowledge that writing is fun and exciting, especially when you want to express yourself vividly. You want to write from the heart, devoid of the standards of journalism. But to some extent, you would have to write based on the conventions of grammar. One of these conventions includes the use of the Oxford comma.

You may be wondering what the Oxford comma is. You may, in fact, have used it before. In this article, we will introduce you to the Oxford comma and why you should be using it in your writing.

The Oxford Comma Defined

The Oxford comma, also known as the serial comma, is the final comma that is placed before a coordinating conjunction in a set of three or more objects. These coordinating conjunctions include “and” or “or.” Editors and writers have varied opinions on whether or not people should use the serial comma. Even its use also differs between and among regional varieties of English. Nevertheless, the comma has been used in various pieces throughout the ages.

Let us provide you with an example:

Sentence 1: John brought us apples, oranges and grapes.

Sentence 2: John brought us apples, oranges, and grapes.


If you look at the Sentence 1 above, the Oxford comma was not used. Hence, we can conclude that the two fruits namely, “oranges and grapes” are considered as one. In Sentence 2, the Oxford comma was used. This changes the whole structure of the sentence. We can safely assume that John brought three different fruits: apples, oranges, and also grapes.

You should note that the Oxford comma is optional, which means you are not required to use it. As a matter of fact, it is not a common practice in countries such as the United Kingdom, South Africa, or Australia. Although it is a standard grammar rule in the United States, it is more common when dealing with non-journalistic forms of prose.

Importance of the Oxford Comma

As we have mentioned earlier, using the serial comma or Oxford comma is entirely optional. However, the meanings of most – if not all – sentences might change drastically without it. This is one of the reasons why the Oxford comma is important.

Let us take for instance several examples presented below.

Sentence 1: Cynthia invited her two bosses, Larry and Bert.

Sentence 2: Cynthia invited her two bosses, Larry, and Bert.

With the omission of a comma, the meaning of the sentence changes completely. For the first sentence, Cynthia invited two people – her two bosses. This is because the absence of the Oxford comma makes it appear that the bosses are in fact, Larry and Bert. However, in the second sentence, Cynthia invited four people – her two bosses, Larry, and finally, we have Bert. The presence of the Oxford comma makes it appear that Larry and Bert are separate entities from the two bosses.

One of the other reasons why the Oxford comma is necessary is so that we could make our thoughts as clear as possible. When writing, the stress or pause which we intend might not be translated fully into text. This might confuse a lot of readers. Let us look at another example where this reason is evident.

Sentence 1: Dimitri drove with his best friend, a doctor and an engineer.

Sentence 2: Dimitri drove with his best friend, a doctor, and an engineer.

If we try to study the first sentence, we may conclude that Dimitri’s best friend is a doctor and an engineer at the same time. This is because the absence of the Oxford comma allows us to think that these two terms (namely, the doctor and the engineer) describe his best friend. However, if we try to add the Oxford comma after the conjunction, the whole sentence forms a new meaning. The second sentence now means that Dimitri drove with three different people – his best friend, a doctor, and also the engineer.

Here is another example where confusion might arise when the Oxford comma is absent.

Sentence 1: She dedicated her speech to her parents, Walt Whitman and God.

Sentence 2: She dedicated her speech to her parents, Walt Whitman, and God.

Basing from the first sentence, it is likely that the speech was dedicated to her parents, namely Walt Whitman and God. This might confuse readers since they could comprehend that her parents’ names are indeed Walt Whitman and God. To avoid confusion and ambiguity, the comma is essential. If we look at the second sentence, it becomes more evident – that the speech was dedicated to her parents, to Walt Whitman, and finally, to God.

To read more about common oxford comma issues and other punctuation errors, you should read Eats, Shoots & Leaves.

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History of the Oxford Comma

Like the comma itself, the origins of the Oxford comma is also ambiguous. But before we do get to know the person who is attributed to this grammar style, we have to give credit to the person who introduced comma. An Italian painter in the 15th century, Aldus Manutius (or Aldo Manuzio as others call him) introduced the concept of the comma in order to separate things.

Horace Hart, on the other hand, is attributed to be the person who introduced the serial comma to the world. Hart is a controller of the Oxford University Press from the year 1893 to 1915. In the year 1905, he published a book entitled, “Hart’s Rules for Compositors and Readers,” which served as a style guide for the employers who used to work at the press. The Oxford comma was included in such rule.

There were others, however, which were attributed to being the one who introduced such concept. Peter Sutcliff credited F. Howard Collins for introducing Oxford comma. It was noted that Collins stated it in his 1912 book entitled, “Author & Printer: A Guide for Authors, Editors, Printers, Correctors of the Press, Compositors, and Typists.” Nevertheless, it was Sutcliff himself who called the Oxford comma as such in his 1978 book regarding the history of the Oxford University Press.

No matter the ambiguous history, there is one thing that is clear – the need to use the Oxford comma. Why not try using it today?

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    There are two interpretations possible for Sentence 2.
    1. Dimitri was accompanied by two people, his best friend who is a doctor, and an engineer.
    2. Dimitri was accompnaied by three people, his best friend, a doctor, and an engineer.


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