noun
accidental work; something done by chance
Refers to a piece of work (often artistic or literary) produced incidentally, without serious intent, or as a casual by-product. The gloss 'two working together' is a rare or obsolete interpretation; the primary meaning is an accidental creation.
この詩は若い頃の偶作で、特に発表するつもりはなかった。
This poem was an accidental work from my youth; I never intended to publish it.
彼のスケッチの多くは偶作であり、計画的な作品ではない。
Many of his sketches are casual by-products, not planned works.
Compound of 偶 (ぐう, 'accidental, by chance') and 作 (さく, 'work, production'). The exact historical derivation is uncertain, but the word is formed from standard Sino-Japanese morphemes.