noun
simple work; repetitive job; unskilled work; menial work
Refers to tasks that are straightforward, often repetitive, and require little skill or training. Can carry a slightly negative connotation of being tedious or low-level.
工場で単純作業を繰り返すのは疲れる。
Repeating simple tasks at the factory is tiring.
彼は単純作業が苦手で、すぐに飽きてしまう。
He is not good at menial work and gets bored quickly.
Compound of 単純 (simple) and 作業 (work, operation). The exact historical derivation is straightforward; the word is a modern combination of these two Sino-Japanese elements.