noun

a small close-knit group of people who do not readily allow others to join them.

his flat became a haven for a clique of young men of similar tastes

coterie,circle,inner circle,crowd,in-crowd,set,group,pack,band,ring,mob,crew,club,society,fraternity,sorority,fellowship,camp,cartel,cabal,junta,caucus,cell,lobby,push,gang,bunch,camarilla