hashtag--or, Beware the octothorp, my son

photo by Charles Hutchins

One of the lighter moments of the Anita Hill talk I attended last month was when the presenter, a revered professor on the campus, told people they could join in on some online conversation at "number sign".... A gentle wave of amusement went through the crowd at the realization that she was actually referring to a Twitter address. And to tell the truth even I, techno last adapter that I am, was a little surprised that she hadn't come across the term "hashtag" in her academic exposure to social media. (She had reached Anita Hill by the simple expedient of an email, after all.) But she had the good graces to laugh along with everyone else at not being up to speed, and so the moment passed more or less without incident.


But it got me to wondering about the term "hashtag", how long it has been with us, and what uses it had in previous times. I thought it would be a short post.


"Hashtag" can be traced all the way back to its ancient sources in, uh, 2007. Apparently, it's pretty well documented that Chris Messina (the open source advocate, not the actor on The Mindy Project)  wondered if the pound or number symbol on the keyboard wouldn't do as well as any as a means of gathering comments into groups, and gradually or maybe not so gradually this became a convention, despite some resistance by people who didn't know an easy fix when they saw one. 

Of course,there's a bit of conflation going on here, as the symbol is really just a hash mark (which Wikipedia tells me is the common term in the British Isles and also that "hash" is a corruption of "hatch", as in crosshatching), the tag being the part that follows the symbol. But, as Paul McCartney said, let it be.

photo by Quinn Dombrowski

As I'm sure has crossed your mind by now, the symbol predates the term by a long shot, and has a lot more meanings than even occurred to me as I started out here. It is the number sign, the pound sign, on a slant, the sharp sign in music, and is used in such far flung fields as mining, chess and scrabble. I liked Wikipedia's example of how it is used in linguistic syntax, where it denotes a sentence that is "semantically ill-formed, though grammatically well-formed. For instance, "#The toothbrush is pregnant" is a grammatical sentence, but the meaning is odd."

Apparently, the actual symbol has its roots in Rome, and in the term libra pondo, which translates into English as 'a pound in weight'. According to an article in Mental Floss, we take the name for the weight from the pondo, but the abbreviation (lb.) from the libra, which as all good astrologists know means "scales" or "balance".

So far, so good. But how does lb. become #, you ask? According to a short piece in the New Yorker by Keith Houston, we can put it down to "the rushed pens of scribes". He tells us that in standard abbreviations, a bar was often cast through the letters, I suppose in a way similar to our putting a period at the end of them, to indicate that they are abbreviations. Interestingly, this bar is called tittle or tilde. typesetters had a standard piece of type with the bar in it, but harried scribes were a little sloppier about it, and the symbol became more abstract. As he tells us about the images below, the left is none other than Isaac Newton's version of the barred lb., while the right is how it appeared in print.

Othmer Library of Chemical History, Chemical Heritage Foundation.

Now you'd think that with all these names and meanings floating around, we wouldn't need another term, wouldn't you? But apparently the scientists at the Bell Laboratories disagreed. According to Dictionary.com, when they modified the telephone keypad in the early sixties, they felt that they needed to give it a more official name, and so came up with "octothorp". "Octo" has to do with the eight ends of the figure, the 'thorpe', well, there are, shall we say, rumors. Interestingly, Blogger doesn't recognize the word octothorp and suggests I use "proctor" instead. It's true that my typing might mangle the spelling of the word, but that's a bridge too far even for me.

And knowing now how these things take off, please don't start calling this: # the proctor sign.

I'm begging you.