The word for today is…
jamboree (noun) – 1. A noisy celebration.
2. A large assembly, often international, especially of Boy Scouts or Girl Scouts.
3. A mass gathering or assembly, as of a political party or association.
Source : The Free Dictionary
Etymology : 1866, “carousal, noisy drinking bout; any merrymaking,” represented in England as a typical American English word, perhaps from jam on pattern of shivaree [Barnhart]. For the second element, Weekley suggests French bourree, a kind of rustic dance. Century Dictionary calls the whole thing “probably arbitrary.” Klein thinks the word of Hindu origin (but he credits its introduction into English, mistakenly, to Kipling). Boy Scouts use is from 1920.