1. (在所爱慕女子的窗下)为(其)唱(或演奏)小夜曲
If one person serenades another, they sing or play a piece of music for them. Traditionally men did this outside the window of the woman they loved.
2. (古典音乐中为小型管弦乐队谱写的)组曲，小夜曲
In classical music, a serenade is a piece in several parts written for a small orchestra.
1. a musical composition in several movements
has no fixed form
Synonym: divertimento
2. a song characteristically played outside the house of a woman