The serial comma: a tiny mark that can save your parents from being popes

Cultures · Published 30 September 2026 Swipe more like this →

In short: The serial comma, or Oxford comma, is the punctuation mark placed before the final conjunction in a list of three or more items. While it is a staple of formal American English, it is often omitted in journalism to save space. Yet, this small mark can either clarify or confuse.

The serial comma is a subject of intense debate among style guides, with no universal standard for its application. It is generally favored in academic, legal, and literary contexts, including guides like The Chicago Manual of Style and the APA style. Conversely, many newspaper stylebooks, such as the Associated Press Stylebook, typically advise against it to conserve space in print.

Proponents argue that the comma provides clarity, especially in complex lists where it prevents items from being misread as appositives. For instance, a dedication to 'my parents, Mother Teresa and the pope' could imply that the writer’s parents are Mother Teresa and the pope. Adding a serial comma after 'Teresa' separates the entities, clarifying the list. However, the mark is not a panacea; in some cases, it can create new ambiguities, such as when a reader misinterprets a list item as an appositive renaming the preceding noun.

The origins of the mark are often linked to 15th-century printer Aldus Manutius, though the specific term 'serial comma' did not gain a distinct name until 1978. Horace Hart, who managed the Oxford University Press from 1893 to 1915, is frequently credited with popularizing its use through his 1905 guide, 'Hart's Rules for Compositors and Readers.' Others, such as Peter Sutcliffe, have suggested that F. Howard Collins was the true pioneer, citing his 1905 book 'Author & Printer.'

Ultimately, the serial comma remains a tool of stylistic preference rather than a strict grammatical rule. When ambiguity persists regardless of punctuation, writers often turn to alternative phrasing, such as rearranging the list or using parentheses, to ensure their intended meaning is unmistakable. Whether to use the mark often depends on the specific style guide one follows or the need to avoid potential misinterpretation in a given sentence.

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