When you are walking down a hallway, street, etc., and you are about to walk into someone, so you both try to maneuver around the other one, and then you end up just awkwardly shuffling back and forth and staring and each other.
Paco: I hate walking through the English wing, because it's impossible to avoid hallmoshing.

Carmelita: Earlier today, I hallmoshed with this adorable guy for like, 10 minutes straight! It was so, like, totally awful because after, I knew I had like, no chance of getting his number...
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