What does colon mean?
The word 'colon' names two quite distinct things that share only their spelling. Most familiarly, it is the punctuation mark consisting of two vertically aligned dots (:), used in writing to introduce a list, a quotation, an explanation, or a clause that develops the idea before it, as well as to separate hours from minutes or chapters from verses. In anatomy, the colon is the largest portion of the large intestine, the muscular tube running from the cecum to the rectum in which water and salts are absorbed from digested food; phrases like 'colon cancer' make this sense prominent in medicine. Both meanings descend from the ancient Greek 'kolon', meaning a limb or member of the body — the punctuation mark was so named because rhetoricians regarded it as a 'member' of a larger sentence, just as the intestine is a member of the body. The standard plural is 'colons'.
A punctuation mark (:) used in writing to introduce a list, quotation, explanation, or amplifying clause, or to separate numbers such as hours and minutes in expressions of time.
"The recipe called for just one unusual ingredient: sumac."
In most modern style guides, no capital letter follows a colon unless what follows is a direct quotation or a complete sentence that stands independently.
In anatomy, the chief portion of the large intestine, running from the cecum to the rectum, in which water and salts are absorbed from undigested food.
"A high-fiber diet is widely recommended for keeping the colon healthy."
The regular plural 'colons' is standard for both the punctuation mark and the anatomical sense; the Latinate plural 'cola' appears occasionally in typographical contexts but is uncommon.
"The manuscript contained too many colons, so the editor replaced several with dashes."
The same Greek word for 'a limb of the body' gave English both the punctuation mark on your keyboard and the longest part of your large intestine.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of colon
Both major senses of 'colon' derive ultimately from the Greek 'kolon' (κόλον), meaning 'limb' or 'member'. Greek grammarians borrowed the term for rhetoric, treating a colon as a limb or section of a longer sentence, and this usage passed into Latin and then into European languages, where the written mark itself took the name by the early modern period. Anatomical use reflects the original bodily sense, since the colon is literally a 'member' of the digestive tract. Related medical terms such as 'colitis' and 'colostomy' share the same Greek root.
How colon is actually used
As a noun, 'colon' has two unrelated everyday senses — the punctuation mark and the intestinal organ — distinguished entirely by context. The plural is normally 'colons'; the Latin-style plural 'cola' occasionally appears in typography discussions but is rare. In formal writing, style guides vary on whether a colon should be preceded by a space, and British usage traditionally places no full stop after a colon introducing a complete sentence.
Easily confused with colon
A semicolon (;) joins two closely related independent clauses, while a colon (:) introduces or emphasizes what follows it.
Despite the similar spelling, 'colony' derives from the Latin 'colonus' meaning farmer or settler, whereas 'colon' comes from the Greek 'kolon' meaning limb or part.