Selfie is a word for something people had been doing for more than 170 years before it existed.

The photographer Robert Cornelius made a daguerreotype of himself in 1839, one of the first photographs of a person. The word took much longer. Its first known appearance is a post on an Australian online science forum on 13 September 2002. The poster, Nathan Hope, described tripping on some steps at a friend's 21st birthday and apologised that the photo of his injured lip was out of focus, explaining that it was a selfie. He later said he hadn't coined it and that it was simply common slang at the time.

The -ie ending fits that origin. Oxford's editorial director, Judy Pearsall, pointed out that Australian English is especially fond of -ie words, and that the friendly diminutive makes an essentially self-regarding habit sound more endearing. Early examples were sometimes spelled with a -y. The hashtag #selfie appeared on Flickr as early as 2004. But Pearsall said use didn't become widespread until around 2012, when mainstream media started using it.

Then it took off. Oxford Dictionaries named selfie its Word of the Year for 2013 on 19 November. Its research programme, which collected about 150 million words of current English from the web each month, showed the word's frequency had risen by 17,000% in a year. The editors said it had gone from a niche social media tag to the mainstream word for a self-portrait photograph. A widely shared picture of the Pope posing with teenagers in August that year was among the images that had helped it spread. Selfie beat a shortlist that included twerk, binge-watch and showrooming.

It became official quickly. Selfie had been added to Oxford Dictionaries Online in August 2013, and by August 2014 it was allowed in Scrabble. The name is new, and still a little self-mocking with that -ie, but the habit goes back to the beginnings of photography.