clannish
/ˈklænɪʃ/Definitions
1. adjective
Having or showing a strong loyalty and sense of belonging to one’s family or group, often to the point of being hostile or unfriendly to outsiders.
“The community was plagued by a clannish attitude, making it difficult for outsiders to gain acceptance.”
2. noun
A person who has this attitude or behavior.
“The clannish individual refused to work with people from other parts of the country.”