noun
evening party; soirée
A formal or semi-formal social gathering held in the evening. Often implies a somewhat elegant or Western-style event.
大使館で開かれた夜会に招待された。
I was invited to an evening party held at the embassy.
彼女は夜会に着ていくドレスを選んでいる。
She is choosing a dress to wear to the soirée.