The Grammarphobia Blog

The octothorpe’s many tentacles

Q: I’ve read that the symbol “#” on keypad buttons is called an “octothorpe.” I believe the term has something to do with a clearing in a village. Can you tell me more about it?

A. The term (spelled “octothorpe,” “octothorp,” octalthorp,” “octotherp,” etc.) first appeared in print in 1974 in the magazine Telephony, according to the Oxford English Dictionary. Here’s the quote: “A few months ago, a story traveled through the Bell System that the familiar symbol ‘#’ at long last had a name: ‘octothorp.’”

The origin of the word, which describes the symbol commonly referred to as the pound key, the number sign, or the hash mark, is uncertain. The most frequently heard explanation is that it was coined by one or more engineers at Bell Telephone Laboratories in the 1960s.

Several people who worked at Bell Labs have written accounts about the term, attributing it to various engineers. The wordsmith (or wordsmiths) who came up with the word, according to the stories, was trying to rename one of the two new symbols (the asterisk and the hash mark) that were added to the telephone with touchtone dialing.

Why an “octothorpe”? The various sources agree that the first part comes from the Greek or Latin word “octo,” meaning the number eight, and refers to the symbol’s eight sides or points. But the sources differ about the second half of the term. Here are some of the suggestions.

One former Bell engineer has said “thorpe” comes from the last name of the American athlete Jim Thorpe. Another has said “therp” is a whimsical ending that sounds Greek. Still another has described the choice of “therp” as a joke because the addition makes the word hard to pronounce.

The OED, meanwhile, speculates that the second half of “octothorpe” may be related to an Anglo-Saxon word (spelled “thorpe,” “throop,” or “thrupp”) that refers to a village or hamlet. (Robert Bringhurst, in The Elements of Typographic Style, notes that the symbol “#” has been used on maps to denote a village, which he describes as “eight fields around a central square.”)

Finally, The American Heritage Dictionary of the English Language (4th ed.) suggests that “thorpe” may come from the last name of James Edward Oglethorpe, an English general who founded the American colony of Georgia.

Michael Quinion, who discuses “octothorpe” in detail on his website Word Wide Words, says it serves no practical purpose to have such an oddball term for a symbol that already has several perfectly acceptable names.

I agree, though “octothorpe” does have one practical purpose—in crossword puzzles!

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