conventicle
/kɒnvɛnˈtɪkəl/Definitions
1. noun
A small group of people who meet secretly, often to discuss or engage in a particular activity, especially a religious group.
“The conventicle of Quakers secretly met on the outskirts of town to discuss their faith.”
2. noun
A gathering of people for a specific purpose, especially a social or intellectual one.
“The literary conventicle at the university was known for its lively debates and discussions.”