synthetic sake
Refers to sake produced by blending alcohol, sugars, and flavorings rather than through traditional brewing. Often contrasted with 純米酒 (junmai-shu, pure rice sake).
Synthetic sake was widely consumed during the postwar rice shortage.
日本酒 is a broad term for Japanese sake, which can include both traditionally brewed and synthetic varieties, but 合成酒 specifically denotes the synthetic type.
Compound of 合成 (gousei, 'synthesis') and 酒 (shu, 'sake'). The term arose in the early 20th century to describe sake made by blending synthetic alcohol with other ingredients.