noun
night school; evening school
Refers to a school that holds classes in the evening or at night, typically for working students or adults.
彼は昼間働いて、夜間学校に通っている。
He works during the day and attends night school.
夜学 is a shorter, slightly more casual synonym for night school, while 夜間学校 is the more formal and descriptive term.
Compound of 夜間 (yakan, 'nighttime') and 学校 (gakkō, 'school').