assembly hall; place of assembly
Often used in compound names like 商工会議所 (chamber of commerce and industry). As a standalone word, it refers to a building or room where meetings are held.
A meeting was held at the chamber of commerce.
This building was once used as the town's assembly hall.
Compound of 会議 (meeting) and 所 (place). The exact historical derivation is uncertain, but the word has been used since the Meiji era for formal assembly places.