The act of just whipping your dick out while talking to a girl that may or may not be interested in doing something with it.
Yelling "Whoop there it is" could potentially be appropriate depending on the setting.
Usually this is appropriate during long boring stories about trips to the mall with her friends, the wnba, reading... etc. which no, especially not you cares about.
If you run in to issues with the reaction, it is usually helpful to say "Whacha gonna do with it? Whacha gonna do with it? Can't do nothin, can't do nothin."
The word is derived from the lyric "Whooop There it is"
Ya bro after the party I was sitting there Veronica and she was telling me about Twilight, or her Uncle's funeral or some shit, anyways I went Will Smith Status.