Onesie, it's all in the name. Forget pyjamas and tracksuits; tops and bottoms are so, like, yesterday. The onesie, on the other hand, is a singular item of clothing in more ways than, er, one.

For anyone still baffled, onesies are basically adult Babygros. They were the most common present given last Christmas – 2012's answer to the Rubik's Cube. It's difficult to know what that says about society, but it doesn't look good.

Anyway, that's not the point. Onesies aren't about how you look, they're about being warm and snugly and toasty of toe. Or at least they were until One Direction heartthrob Harry Styles and socialite model Cara Delevingne were spotted sporting them. (For those who care, Harry favours the traditional Norwegian OnePiece, while Cara prefers an animal-inspired Japanese version called a Kigu.)

Suddenly, onesies were all about sex and commercialism. To recap: onesies were comfy loungewear, then they were cool and worn by students on nights out, then they were Christmas 2012, and now, well, they're dead. Officially over, and it's all the fault of Nick Clegg.

Baffled again? Well, Clegg has a radio show, which is brave and stupid, but mostly stupid, because anyone can call in and ask him anything, and he's just got to answer, there and then, like a normal person. Case in point: just 30 minutes into his first show some joker (who turns out to be an Old Etonian ex-Lib Dem intern) calls up and asks the question on everyone's mind: does Mr Clegg own a onesie? And he only goes and says: "Yes."

You can see how it happened. In that split second, put on the spot, on live radio, Clegg obviously recalled the importance of being "down with the kids", and reasoned that what could be more down with the kids than dressing like one? But, as anyone who saw William Hague in a baseball cap knows, there's nothing worse than a politician trying too hard. Back to pyjamas it is then.