We live in an age of the dress. Should “age” and “fashion” appear irreconcilable terms — what with the latter traditionally being in possession of a gnat-like attention span — then rest assured: fashion has slowed down. Time was what was in one season was out the next, what was hot usurping what was not: hemlines up and down like Belle de Jour’s YSL drawers.

Blame the democratisation of the catwalk, instant virtual access meaning no top-down, biannual reveals. Blame Phoebe Philo’s “old Céline” promoting the revolutionary idea of women wearing what felt comfortable or Alessandro Michele at Gucci with his notion that one’s wardrobe might evolve rather than lurch between extremes. Call it eco-awareness, call it post-recessionary ennui, call it sheer bloody exhaustion, but frenetic newness has been replaced by what the Guardian’s Jess Cartner-Morley has referred to as the “five-year trend”. And relax . . . into dresses . . . for what seems like forever.

Not just frocks but a particular form of frock: midi-length (around since spring/summer 2014), tea-dressy (wafting back a couple of years later), a tad tent-like (behold, the new modesty). If you’re a Gen X-er, like me, then you’ll resemble your mother back in the late Seventies/early Eighties.

Sometimes it’s a ‘that dress’, sometimes it’s a ‘the dress’, sometimes just dresses

As a look, it’s ostensibly sexless, but not without erotic frisson given that chaps harbour a certain penchant for “Come to Mummy” appeal. Matters had been all Princess Di. However, this season we’re more Princess Anne, upcoming as a style icon in The Crown, and very much “new Celine” gone really old Céline. (Idiot’s guide: add heeled knee-boots.)

Still, there’s always a frock of some sort. In the Nineties it was Hervé Léger’s bondagey bandage dress; in the Noughties, Roland Mouret’s body-con Galaxy. Sometimes it’s a “that dress”, sometimes it’s a “the dress”, sometimes just dresses. Back in Milan in September, Jennifer Lopez donned a “that dress” to close the runway for Versace’s spring/summer 2020 show: a version of the jungle confection she sported to the Grammys in 2000. This original frock was searched for so ardently that Google was famously forced to create Google Images to satisfy demand.

This dress proved a “that dress” because it spawned what Planet Fashion refers to as “a moment”, securing notoriety for Donatella Versace in a way that Elizabeth Hurley sallying forth in safety pins had done for her brother. Never mind that said dress had already been donned by Amber Valletta, Donatella herself, and Ginger Spice. These weren’t moments. A month later, South Park’s Trey Parker wore an imitation of it to the Oscar’s —moment confirmed.

September’s reboot exposed more flesh, while appearing less naked; a feat given that the actress hoisted both halves aloft to reveal her crotch, demure-ish Sheela na gig-style. It looked all right in motion, if by “all right” one means sensational, amazing, a moment, etc. In stills, there’s a certain iron to the Lopez jaw suggesting a stream of consciousness that runs: “Christ, I’m 50, and basically naked in front of the entire world. Maybe that’s why I play a stripper in my latest film rather than, say, Hedda Gabler? I’d like a biscuit. Remember biscuits?”

J-Lo’s strut garnered $9.4 million worth of media mentions and engagement, according to The Business of Fashion. Translation: it’ll shift scent and sunglasses. However, this “that dress” made no sense whatsoever in terms of current dresses.

For these, we need to see “the dress”, aka the £39.99 Zara polka-dot number that gained a lemming-like following during summer 2019. This sack-like affair boasts 26,000 Instagram followers @hot4thespot, reportedly contributing to sales for Inditex, Zara’s parent company, growing by 5 per cent over a six-month period.

In tribute/homage/knock-off terms, #spottyfrock may have started life as the bastard child of the £1,225 Alessandra Rich number worn by actress Abigail Spencer to the Markle/Windsor nuptials, later taken up by the Duchess of Cambridge. Only Zara’s appears to have melted.

Either way, this hit marked the apotheosis of mom dressing. My favourite theory was columnist Lucy Mangan’s that it constituted “history’s greatest democratic dress”, being universally unflattering on everyone. As I write, it has been reissued in autumnal hues at £49.99.

However, in mid-August, m’learned friend The Times’s Fashion Director Anna Murphy called it for another dress. All hail, Zara’s £59.99 hot pink, metallic, ankle-grazer: “one part Jane Eyre to one part Saturday Night Fever”— and totally Vampire’s Wife, the modish frock brand fronted by Mrs Nick Cave, with designs at £1,600 a pop.

On the one hand I was flattered, having already invested; on the other, I was incensed — this being “my dress”. Fitted, flattering, and ravishingly oddball, it was perfect for the VW, Batsheva, Saloni modest-dressing-with-a-partyish-twist posse. Only they were all on hols, meaning that it is “the dress” only in the sense that I own two. Seek it out on eBay, suckers.