from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun The symbol (#).

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun The hash or square symbol (#), used mainly in telephony and computing


from The American Heritage® Dictionary of the English Language, 4th Edition

[Coined in the 1960s by researchers at Bell Telephone Laboratories : octo– (probably in reference to the eight endpoints of the lines in the symbol) + -thorpe (perhaps from thorp, in reference to the resemblance of the symbol to a village surrounded by fields, or after James Francis Thorpe, because one of the researchers was an advocate of the restoration of Thorpe's Olympic medals).]

from Wiktionary, Creative Commons Attribution/Share-Alike License

Origin disputed. Reportedly a jocular coinage by Bell Labs supervisor Don Macpherson in the early 1960s, from octo- ("eight"), with reference to its eight points, + -thorpe (after 1912 Olympic medalist Jim Thorpe, in whom Macpherson was interested). However, Doug Kerr attributes octatherp to a practical joke by engineers John C. Schaak, Herbert T. Uthlaut, and Lauren Asplund upon himself and Howard Eby.


  • The term octothorpe was coined by engineers at Bell Laboratories in the early 1960s, who wanted a name for one of two non-number function symbols on the first touch-tone keypads the other was the *, which they called a sextile.

    The Guardian World News

  • The octothorpe is the essential symbol in the formation of a hashtag, a marker that allows 140-character tweets to be grouped together by subject

    The Guardian World News

  • Once again, Quinion's World Wide Words explains the history: "octothorpe" was Bell Labs jargon for one of those two function keys on touch-tone telephones that got labeled with symbols instead of numbers.

    Archive 2008-05-01

  • There is also a deep look at the @ symbol's new-found stardom, the octothorpe enjoying a new lease of life renamed as the "hashtag" in Twitter parlance, and the secretive pilcrow.

    Internet picks of the week

  • Robert Bringhurst's The Elements of Typographic Style says the word "guillemet" honors the the sixteenth-century typecutter Guillaume le Bé. octothorpe: #

    Archive 2008-05-01

  • Some of my writing-group partners are no doubt baffled by my apparent love for the octothorpe.

    Archive 2008-05-01

  • The symbol on the “pound” key (#) is called an octothorpe.

    10 Weird Science Facts You Didn’t Know

  • I wonder, however, about the explanation for octothorpe given at the linked page in the entry above. NEOLOGISMS.

  • I wonder on what basis the AHD associates Oglethorpe with octothorpe. NEOLOGISMS.

  • And here's a funny discussion of the etymology of octothorpe. NEOLOGISMS.


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  • In the pound versus hash war, there was no winner-- octothorpe took the prize.

    January 24, 2007

  • Poor number sign and tic tac toe didn't even get participant ribbons. And our old buddy at sign wishes he could have a cool name like all his friends.

    January 25, 2007

  • Ah, let's give old at sign some strudel as a consolation!

    December 13, 2007

  • Npydyuan! You've been away for a bit too--welcome back. :-)

    December 13, 2007

  • Thanks! :-D

    December 14, 2007

  • see hash

    July 23, 2008

  • This mark has several common names: 'hash', 'hatch', 'pound sign', and 'octothorp' among them. The name "pound sign" is an Americanism that causes some confusion in countries that use the pound for currency.

    It was also noted that the # is a medieval abbreviation for Latin "numerus" - it is a cursive 'n' with a horizontal slash through it, much modified and abstracted.

    One possible derivation of the name "octothorp" was provided by Charles Bigelow:

    ... old English "thorp" meant 'hamlet' or 'village' (I'm not sure of the difference, except maybe hamlet is smaller, as its apparent diminutive suffix would suggest), and is derived from a much older Indo-European word *treb- for 'dwelling', which turns out to mean 'beam' or 'timber' in Latin "trabs", winding up as "trave" in Anglo-Latin, like "architrave" - the beam resting on a column, or "trab-" as in "trabecula" - a small supporting beam or bar. As Voltaire said, etymology is a science in which the vowels count for nothing and the consonants for very little.

    So, maybe "octothorp" means "8-beams", which makes a kind of sense if we take the 8 projections to be the thorps, or trabs or traves. Though it's only a "quadrathorp" if we think that the beams connect.

    Another explanation has it that the octothorp is a "thorp"' surrounded by eight cultivated fields.

    July 23, 2008

  • "Enter your password then press octothorpe!"

    FYI- This word is so scarcely used that even Firefox's spellchecker doesn't even recognize it.

    September 21, 2008

  • A discussion on the origins of this word can be found at World Wide Words here. In Slovene, by the way, this mark is called lojtra, the colloquial word for "ladder" (from German Leiter) – which makes me think that we sometimes call it "the ladder sign" in English, don't we?

    September 26, 2008

  • I Have To Go. Look at the time.

    LOVE YOU!!!!!!!!!!!!!!!!!!!!!!!(Google?)


    April 28, 2009