also: したさく
na-adjective, noun
poor quality; inferior goods; shoddy
Describes something of low quality, poorly made, or inferior. Can be used as a noun or na-adjective.
この店の商品は下作なものが多い。
Many of the products in this store are of poor quality.
彼は下作の時計を買ってすぐに壊れた。
He bought a shoddy watch and it broke immediately.
The kanji 下 (lower) and 作 (make) combine to suggest something made to a low standard. The exact historical derivation is uncertain, but the meaning is transparent from the components.