In a sea of utterly beautiful women wearing spectacular designer dresses, she walked up the red-carpet stairs. Her dress, at the 2011 Metropolitan Museum of Art Costume Institute gala, was by Stella McCartney.

It was a dark-teal number with embroidered silver stars running from the waist to a short train and it was teamed with heels by Sergio Rossi and jewellery by Cartier.

Her name is Madonna and she looked elegant and hot.

But, in an aside to the assembled press, she was reported to have said, "I feel fat in my dress."

Pardon me? You feel what? You feel ... fat?

Madonna, a woman whose fitness regimen would frighten a paratrooper, feels fat.

Website US Weekly reported the comment and in a funny way the remark comes as no surprise. Women say this all the time - no matter what size they are.

More Rubenesque ladies, and I say this with some experience, live in a world teeming with judgments about their size.

As a result, some believe what advertising, gossip magazines and fashion designers favour as the ideal size. They think they are fat.

But then, not every slender woman lives smug in the belief she is slim and magnificent. Some of them say they are fat, too. They put on tiny dresses and swish this way and that but nothing can stop them telling whoever is nearby that there's a chubster inside the gown waiting to burst out. Women of absolutely every size, from chubby to skinny, stand in front of a mirror every so often (or every day) and say, "I feel fat in my dress."

When Madonna says it at a star-studded gala ball with people such as Giselle Bundchen, Miranda Kerr, Penelope Cruz, Blake Lively and Sarah Jessica Parker walking past in swathes of gorgeous silk, tulle and sequinned satin, the meaning of the word "fat" becomes something else.

It's a crutch, a term to fall back on when you are not feeling your best. We say it among friends and they say, supportively, "No way. You look fantastic. You are not fat."