sociable: a party of people assembled to promote sociability and communal activity
party: a group of people gathered together for pleasure
millennium: (New Testament) in Revelations it is foretold that those faithful to Jesus will reign with Jesus over the earth for a thousand years; the meaning of these words have been much debated; some denominations (e.g. Jehovah's Witnesses) expect it to be a thousand years of justice and peace and happiness