Convocation (noun)

A large formal assembly of people, especially one summoned for a particular purpose.

Origin:

Late middle english. from latin convocatio, from convocare "call together".

Examples:

1. The convocation was held to discuss important issues facing the community.
2. The convocation of religious leaders was attended by thousands of people.
3. The convocation of politicians from different countries was a historic event.
4. The convocation of alumni was a nostalgic reunion for former classmates.
5. The convocation of scientists was a forum for exchanging ideas and presenting new research.