Knot
Today’s edition of The New York Times’ Strands 🔗 turned out to be themed around group words like “swarm” and “colony”. One of those words was “knot”.
Britannica defines a “knot” 🔗 as:
a group of people who are standing or sitting close together
So a group of people social distancing would not be a knot, but they could be a knot if they’re not doing that.