Bisexual Chic refers to the act of pretending to be bisexual in order to attract attention and often time members of the opposite sex as well. It more common among women than men.
Did you hear?
Janie came out of the closet as a bisexual!
She's not really bi, she's just pretending... She's Bisexual Chic.
A cultural trend where it is 'cool' to claim to be a bisexual even if you are not just so you can get attention. Much more common in women than in men. It is often done to get a rise out of people.
Please note though that not everyone who claims to be bisexual is saying it for attention; there are real bisexuals out there.
Britney Spears and Madonna kissing on MTV is a good example of Bisexual chic.