According to the Merriam-Essman Dictionary (that would be me), a broad is defined as "a real woman." A woman who can hang with the guys when necessary but is still the best friend her girlfriends could ever wish for. A broad likes to eat and drink and laugh out loud. A broad is not offended by ribald or salty humor. In fact, she can curse with the best of them. A broad knows who and what she is and although some people may say she's crass or unladylike, she knows exactly when and how to use her feminine wiles—and when and how to tell those same people to go shove it.
A broad isn't a little girl; you know, a grown woman who still comports herself as though she's a frilly 9-year-old on a playground full of boys. She doesn't play a helpless, tragic, waif thing. She's not a fragile, delicate flower that's going to break if you look at her the wrong way. She's not expecting somebody to save or rescue her. She can take care of herself, thank you very much. It's not that she doesn't need or want a man—she frequently does, and she frequently has one—but her happiness and well-being aren't contingent upon having it. She'll go to casinos and play poker, she'll go to saloons and knock 'em back, she'll go to ballgames and scream and shout, and know exactly what she's screaming about.