noun
easy course; easy A; bird course
Colloquial term used by students for a university course that is easy to pass or get a good grade in. Often used in contrast to 難単 (なんたん, difficult course).
来学期は楽単ばかり取ろうと思ってる。
I'm thinking of taking only easy courses next semester.
あの先生の授業は楽単で有名だよ。
That professor's class is famous for being an easy A.