noun
dupion; double cocoon
A double cocoon formed jointly by two or more silkworms, producing a coarse, irregular silk. The term is technical and used in sericulture and textiles.
玉繭から取れる糸は節があって独特の風合いがある。
Thread obtained from dupion cocoons has slubs and a unique texture.
noun
General term for a silkworm cocoon. In everyday contexts, 繭 (まゆ) is more common; 玉繭 is used especially when the spherical shape is emphasized or in technical descriptions.
蚕が作った玉繭を集めて糸を紡ぐ。
We collect the cocoons made by silkworms and spin thread.