a small group of people who spend their time together and do not allow others to join them (Oxford)
a small group of people who spend their time together and do not welcome other people into that group (Cambridge)
The club is dominated by a small clique of intellectuals. (Oxford)
Our golf club is run by a very unfriendly clique (of people). (Cambridge)
a clique of intellectuals
unfriendly clique (of people)
Clan
Gang
Individual
Cliquey