In November 2005, the American edition of the Oxford English Dictionary declared that 'podcast' was the word of the year.
Squaring up to the year's vocabulary heavyweights, the compound concerns of 'bird flu' and the number-crunching craze 'sudoku', podcast - a hybrid of iPod and broadcast, a shortmanteau of sorts - claimed the title, despite the fact that the only people who ever listened to them were audio geeks who understood how the internet worked.
Nine years on, and nine episodes into Serial, the podcast is once again the toast of the town. So fashionable, in fact, that Vogue, the veritable bible of chic, this week published a list of podcasts to binge on while Serial took a week off for Thanksgiving.
At its core, Serial is a story of four people, and two of them have never even heard it; first and foremost, there's Hae Min Lee, an 18-year-old school girl who was strangled to death in Baltimore in 1999. Then there's Adnan Syed, the ex-boyfriend convicted of murdering Hae in 2000, who's been protesting his innocence in prison ever since, without any access to the internet.
Then comes Sarah Koenig, a seasoned radio journalist investigating Syed's conviction and potential guilt or innocence, finding witnesses and evidence to support both.
And, finally, there's you. And me. And millions of others all over the world.
Listening in every Thursday to savour over each new lead and twist and turn the case takes over early-morning commutes or early-evening ironing, allowing this 15-year-old cold case to unravel intimately in our ears with gently-playing piano music.
Since its debut in October, Serial has become a cultural phenomenon.
A spin-off of the popular National Public Radio programme This American Life, a collection of non-fiction narratives presented by the disarmingly charming Ira Glass, Serial became the fastest ever podcast to hit 5 million downloads on iTunes.
To put those figures into context, it took This American Life, on which Sarah Koenig also works as a producer and arguably NPR's flagship show, four years of weekly broadcasts to build an audience of 1m listeners. Serial did that in four weeks - and it got them to come to it.
Just why Serial has struck such a chord with audiences worldwide is a mystery as rich as the one it is trying to unravel, and one which radio producers everywhere will soon be trying to emulate; without a doubt, it's a sensational thriller, with a likeable underdog hero who might also be a brilliantly conniving socio-path. The case and its legal minutiae is pored over by Koenig's arch narration, teasing and drip-feeding facts and revelations, making wry asides when her frustration and uncertainty bubble up to the surface. But it's not all too different from a typical episode of This American Life, just spaced out over three months. Perhaps it's because it's his American life sentence, with Syed so steadfastly stating his innocence for so long, and the evidence teasing your judgements one way and the other.
Either way, when Serial reaches its conclusion with episode 12, whether Syed's innocence will be proven or guilt confirmed, the real winner is podcasting as a medium.
Those who have been listening for the last nine years might find it novel that it took something like Serial to push podcasts to the forefront of media consumption, and while it has tapped into the mainstream, there's been rumblings of a revolution for quite some time.
Roman Mars, whose architecture and design podcast 99% Invisible recently played a sold-out live show at Dublin's Sounds Alive festival, is the poster boy of the indie producers. 20 million downloads of his explanations on flag designs and nautical camouflage later, three times he has asked listeners to contribute money so he can keep making his show.
To date, those fans, spurred on by loyalty and appreciation for different storytelling that's made well have coughed up almost €1m so a nerd in California can tell them what makes a good fire exit.
One of NPR's own, financial journalist and another This American Life alumnus Alex Blumberg, recently gave up his comfortable job presenting the channel's Planet Money programme to start his very podcasting empire, Gimlet Media.
Blumberg believes there's a market for a subscription library for podcasts - think Netflix for your ears - and wants to get in on the ground floor. Naturally enough he's serialising the whole thing in a podcast called StartUp.
Last week, Sarah Koenig asked fans to consider donating money for a second season of Serial. Whether or not a second story told across 12 episodes can repeat the success of this water-cooler whodunit, the real revelation is how a free-to-listen-to podcast can shake up the entire media industry.