noun
failed student; student who must repeat a year
Refers to a student who has failed to meet the academic requirements to advance to the next grade or graduate, and must repeat the year. Often used in school contexts.
彼は試験に落ちて落第生になった。
He failed the exam and became a student who has to repeat the year.
落第生にならないように、毎
I study every day so that I don't become a student who has to repeat a year.