The Grammarphobia Blog

Serial number

Q: While reading your blog, I notice that you place a comma before “and” in a list of things. For instance, “in the laundry hamper, on the bathroom sink, and under the bed.” I have always thought that it was incorrect to place a comma before the “and” at the end of a series. Where did I get that?

A: The final comma before “and” in a series is optional. It’s sometimes called the “serial comma” or the “Oxford comma” (because it’s a staple at the Oxford University Press).

The use of the serial comma is not incorrect. We don’t know how you got this impression, but we can guess.

There’s a popular misconception that a comma represents a missing “and,” which would make that final comma redundant. This isn’t true, as we pointed out on the blog last year.

Although the serial comma is optional, many publishers and authors (we’re among them) prefer to use it because the comma can add clarity to a series.

This helps when the list includes phrases rather than single words. Example: “His favorite foods are apple pie, bacon and eggs, and mashed potatoes.”

A final comma can also help to avoid putting terms in apposition—that is, identifying them with one another. Example: “He consulted two top oncologists, his uncle and his best friend.”

Are the oncologists his uncle and his friend? If not, use a comma before “and.”

We used a similar example in a posting a couple of years ago. As we said then, a sentence like this cries out for a clarifying comma: “The biggest influences on my career have been my sisters, Martha Stewart and Oprah Winfrey.”

See what we mean? A serial comma can make a big difference.

R. W. Burchfield, writing in Fowler’s Modern English Usage (revised 3rd ed.), agrees: “The ‘Oxford comma’ is frequently, but in my view unwisely, omitted by many other publishers.”

Many news organizations, including the Associated Press and our old boss, the New York Times, don’t generally use serial commas.

When the two of us worked for the Times, we naturally followed the house style. But we think the serial comma is a good idea. That’s why we use it on our blog.

While we’re discussing commas, we should mention that the word “comma” referred to a small piece of a sentence when it entered English in the late 16th century, but it soon came to mean the punctuation mark at the end of the piece.

Although English adopted the word from the Latin comma, it’s ultimately derived from the Greek komma (literally, a piece cut off), according to John Ayto’s Dictionary of Word Origins.

Ayto adds that the Greek verb koptein (to cut) gave Russians the word kopeck and probably gave English the word “capon.” And with that, we’ll cut this off.

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