(among American Indians of the northern Pacific coast, especially the Kwakiutl) a ceremonial festival at which gifts are bestowed on the guests and property is destroyed by its owner in a show of wealth that the guests later attempt to surpass.
The dedication and raising of a totem pole is accompanied by a great potlatch, a public feast often involving lavish gift giving.
Now here comes everybody, and they're bringing their own dialects to the online potlatch.
British Dictionary definitions for potlatch
(anthropol) a competitive ceremonial activity among certain North American Indians, esp the Kwakiutl, involving a lavish distribution of gifts and the destruction of property to emphasize the wealth and status of the chief or clan
(US & Canadian, informal) a wild party or revel
C19: from Chinook, from Nootka patshatl a giving, present