Don’t Pound My Octothorpe

pound-sign-hashtag-numberIf you want to spark a conversation at your next social event, ask everyone the proper name for this symbol: #. Most North Americans will probably say pound sign or perhaps number sign. It helps to have an international audience, since a person from the UK will likely call it the hash symbol. Lately, the world of Twitter (and other social media) has made extensive use of # to tag keywords, referring to it as the hash mark used to create hashtags. A musician might claim that it is the sharp symbol from musical notation but closer examination reveals that the sharp symbol is quite different.

The AT&T engineers working on the original DTMF system adopted the name Octothorpe for this symbol. There are various explanations and anecdotes that have developed over the years concerning how this happened. Various forms of spelling show up in the literature (octatherp, octothorp, etc.). Doug Kerr’s story is particularly interesting and available on the internet (see below). There are US Patents that use the word “octothorp” to refer to the # symbol. Patent number 3920926 uses “octothorp” for # and “sextile or asterisk” for the * symbol. The term sextile never caught on at all.

For amateur radio usage (North America bias), I hear mostly pound for # and star for *. I suspect that will not change any time soon.

– Bob K0NR

Wikipedia entry for the number sign (#):

The Symbol on the “Pound” or “Number” Key (#) is Also Called an Octothorpe

The ASCII Character “Octatherp”, by Doug Kerr

The post Don’t Pound My Octothorpe appeared first on The KØNR Radio Site.

Bob Witte, KØNR, is a regular contributor to and writes from Colorado, USA. Contact him at [email protected].

2 Responses to “Don’t Pound My Octothorpe”

  • Tom Kb3hg:

    The original patent holder was a ham for the DTMF. I saw a news paper clipping of him holding a check, first installment buying the patent from him hanging in his office.

  • Bob KK5R:

    This is from Merriam-Webster:

    Stories abound about who first called the # sign an “octothorpe” (which can also be spelled “octothorp”). Most of those tales link the name to various telephone workers in the 1960s, and all claim the “octo-” part refers to the eight points on the symbol, but the “thorpe” remains a mystery. One story links it to a telephone company employee who happened to burp while talking about the symbol with co-workers. Another relates it to the athlete Jim Thorpe, and a third claims it derives from an Old English word for “village.” If the plethora of theories leaves your head spinning, you might want to take the advice of the wag who asked (poetically),
    “Can we simply just say,
    Ere it spoils your day,
    It’s the thorp between seven and nine?”

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