veselje

1. joy; merriment; gaiety
   Deca su skakala od veselja kad je pao sneg. — The kids jumped for joy when it snowed.
   U kući je vladalo pravo veselje. — The house was full of real merriment.
2. celebration; party; festivities
   Svadbeno veselje trajalo je do jutra. — The wedding celebration went on until morning.
   Posle utakmice je počelo veselje na ulicama. — After the match, celebrations broke out in the streets.

In the sense of a celebration it very often refers to a wedding: svadbeno veselje.