noun
Literally 'night earning'. Can refer to any legitimate night job, but also used euphemistically for burglary or other illicit nighttime activities. Context determines the meaning.
彼は昼間は学生で、夜稼ぎとしてコンビニで働いている。
He is a student during the day and works at a convenience store as a night job.
警察は連続夜稼ぎ事件の犯
The police are pursuing the perpetrator of a series of burglaries.