A person (usuallyfemale) who plays down the fact that they are wearing a fitbit, while simultaneously showing it off to everyone within hearing range of their upper-middle class voice.
Mindy: Hey Danae, is that a fitbit?
Danae: Oh, yes it is... It cost me $300 and it's the latest model, AGAIN, but I just use it to monitor my sleep patterns.
Mindy: Oh, Ok.
Danae: Ughh OMG, I'm at 6500 steps and Tabatha is at 8000. Now I will have to speed walk around Whole Foods in my yoga pants, just to get to my calorie target.
Mindy: Oh, Danae. You are such a fitbitch.
A greeting exchanged on the Jewish Sabbath (or any other day of the week).
One party to the greeting exclaims "Shabbat fistbump!" and pounds the other person's fist.
An energizing upgrade from the traditional Shabbat handshake.
Person 1: Shabbat shalom (peaceful Sabbath) my friend, how was your week? (extends hand)
Person 2: Shabbat fistbump, dude!!! (extends closed fist)
Person 1: (pounds it) That was so much more fulfilling than a regular handshake.