Describing something that has the romantic and/or sexual attraction to both genders. Although it was once a word used almost solely to describe someone who ACTUALLY is bisexual, it has come to also mean attention-seeking, scene kid.
Please, unless you are actually bisexual, don't come out as one. Typically, people who aren't and do, will say that they are straight again soon after. This has already lead to the much of the LGBT community to hate on bisexuals and others outside of it to think being LGBT is a choice.
Being LGBT isn't a choice, so stop acting like it.
Person 1: Zach is dating Samantha.
Person 2: Wait, I though he dated Stan. Isn't he gay?
Person 1: Nope he's bisexual.
Scene kid 1: yah im totaly bisexual now c:
Scene kid 2: o rly? so u wanna go out sometime?
Scene kid 1: nope i only date boys. dating girls is gross XD
Actual bisexual: Shut the fuck up.