Wikipedia
Barowari refers to the public organisation of a religious or other festival, mainly in West Bengal. This is extensively used for Durga Puja. The word "Barowari" came from the words "baro", which means 12, and "yari" (friendly connection). Much earlier in 1790, 12 Brahmin friends in Guptipara, Hooghly, had decided to institute Community Puja. Subscriptions were raised from neighbours. Thus started baro-yari or Barowari Puja in Bengal which gained popularity in leaps and bounds. Initially, Durga Puja was an occasion for the rich Babus of Kolkata, later individual initiatives declined as collective enterprises came to replace it.
In more recent times, the nomenclature ‘barowari’ is being replaced by ‘sarbajanin’ (meaning all inclusive). The Barowari festival is the opposite of household festival organised privately, but often allowing the participation of outsiders. The Barowari festival is organised with funds raised from the public at large through donations or subscriptions.