<P> The use of the term "fascinator" to describe a particular form of late 20th - and early 21st - century millinery emerged towards the end of the late 20th century, possibly as a term for 1990s designs inspired by the small 1960s cocktail hats designed to perch upon the highly coiffed hairstyles of the period . Although they did not give the style its name, the milliners Stephen Jones and Philip Treacy are credited with having popularised and established fascinators . </P> <P> Today, a fascinator is worn on occasions where hats are customary, sometimes serving as an evening accessory, when it may be called a cocktail hat . It is generally worn with fairly formal attire . In addition, fascinators are frequently worn by women as a Christian headcovering during church services, especially weddings . </P> <P> A substantial fascinator is a fascinator of some size or bulk . Bigger than a barrette, modern fascinators are commonly made with feathers, flowers or beads . They need to be attached to the hair by a comb, headband or clip . They are particularly popular at premium horse - racing events, such as the Grand National, Kentucky Derby and the Melbourne Cup . Brides may choose to wear them as an alternative to a bridal veil or hat, particularly if their gowns are non-traditional . </P> <P> At the wedding of Prince William and Catherine Middleton in April 2011, various female guests arrived wearing fascinators . Among them was Princess Beatrice of York, who wore a piece designed by the Irish milliner Philip Treacy . The unusual shape and colour caused quite a media stir and went on to become an internet phenomenon with its own Facebook page . Princess Beatrice used the publicity to auction it off on eBay, where it garnered 99,000 euros for charity . </P>

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