They are the ones that form the tight circles at receptions and allow only the few they consider worthy to break in.

FORBES: Advice For New Graduates

Into the chaos, the fumbling in the dark, an order is imposed as people form circles around performers, a troupe of acrobats, jugglers and escape artists, a comedian, a group of musicians, a story-teller... this is trial by public jury: if the performance falls flat, the tricks fail to amuse or the stories to amaze, the crowds move on.

BBC: Djemaa el Fna, the beating heart of Marrakesh

When they reach a village, the bell ringers form concentric circles in the town square, ringing fiercely until the residents offer them food and a chance to rest before they continue their journey.

UNESCO: Culture

These small classes and lab work encouraged students to form tight friendships, but Mr. Holmes remained outside those inner circles for the most part, one person who took several upper-level classes with him said.

WSJ: Shooting Suspect's Behavior Provided Few Clues