The new word has been coined for the growing number of straight women who flirt with bisexuality. It refers to people who have a sexual preference but refuse to be bound by it.
"Women are often more open to these experiences when they reach their 40s and are more confident with their sexuality. If an opportunity presents itself they may think "why not", particularly if they have come out of a long relationship," the Daily Mail quoted Psychologist Dr Cecelia D''Felice as saying.
Twice-married Barrymore, who has admitted having flings with women, has been quoted as saying, "Being with a woman is like exploring your own body, but through someone else."
Actress Lindsay Lohan, 24, is among younger flexisexuals who see it as ''on trend''.
D''Felice admitted flexisexuality had become fashionable as a result of its recent celebrity endorsement, but said it had always existed.
"Women are more fluid about their sexuality than men and are more likely to be attracted to people rather than a certain gender," she said.
A third of 6,000 women surveyed by Coco de Mer said their favourite fantasy was to have sex with a woman.
Sam Roddick, 39, founder of erotic boutique Coco de Mer, said, "It acknowledges the huge number of straight women who do not want to label themselves bisexual and yet may have kissed a girl or fancied their best friend."