(FORTUNE Magazine) – Manufacturers call them body shapers, smoothers, slender slips, and heaven knows what else. ''We don't use the G-word around here,'' says Peter Velardi, chief executive of VF Corp's Vanity Fair, the lingerie maker. But call it Ishmael, it's still a girdle, and the hottest thing in underwear. Says Kingsley J. McAlpine, senior VP for sales and marketing at competitor Lily of France, a Bestform Foundations subsidiary: ''Everything in the 'control' category is taking off.'' In the past year the company expanded its line of ''control bottoms,'' as briefs and panty girdles are known in the trade, from two styles to ten. In six months, Vanity Fair sold $10 million at retail of Slender Slips, its name for lace-trimmed Lycra half slips and full slips. Three trends have come together to spur sales: technology, fashion, and gravity. Thanks to Lycra -- a lightweight, Du Pont-made elastic that stretches but doesn't deteriorate as fast as rubber did -- garments can be made that offer all the suck-it-in power of the traditional corsets without looking, or weighing, like them. As a result, very young women are going dancing wearing lace-covered panty girdles instead of skirts. Madonna is responsible for this, having encased herself in those pointy bras -- she can etch glass between numbers -- and elasticized biker shorts that French designer Jean-Paul Gaultier created for her. Says Jean Gottdiener, divisional merchandise manager for intimate apparel at Saks Fifth Avenue: ''In the past, rock stars have led ready-to-wear. Now, the lingerie market through Madonna has really inspired ready-to-wear.''

Last, the short, tight, knitted skirts so popular now demand a firm bottom and even firmer thighs. And aging boomers ain't as firm as of yore. They're shelling out $36 to $45 for these slimmers and shapers for the same reasons women always bought girdles: to have a smooth line under their clothes. Something else hasn't changed either: The damn things still ride up.