It makes me wonder how many times I've heard it in the past and thought they were talking about the hair on men's faces. I had never heard that before and now I'm hearing it all the time.
It's like when you learn a new vocabulary word and all of a sudden it pops up in your everyday encounters. Like I learned "bete noire" and I've seen it at least three times in the last month. Look it up if you don't know the deffy but maybe you've known all along. I wonder what other slangs you know that I've never heard of?