Juice vs. Cider: What’s the Difference in Japan?
What cider means differs by country, and in Japan, the word サイダー generally refers to sweet drinks containing carbonated water, citric acid, and fruit flavoring, as I wrote in this article.
Hearing that, you may be confused, but that is not all. As you might have noticed before, some Japanese people also use the word juice/ジュース differently from native English speakers.
Japanese Juice vs. Cider
So as not to be misunderstood, in Japan, too, for beverages, juice/ジュース usually refers to the liquid squeezed from fruit or vegetables or 100 percent fruit/vegetable juice.
Nonetheless, quite a few Japanese, including me, unconsciously use the word for soft drinks, in which sense, juice even includes carbonated beverages, such as cider and cola drinks.
To be correct, the Japanese term for soft drinks other than juice (such as green tea, coffee, fruit & vegetable beverages, soda pop, and mineral water) is 清涼飲料水.
But since many Japanese beverage makers once sold such soft drinks under the name of juice (as seen in 缶ジュース/canned juice, meaning canned drink), the trace remains, and quite a few people still use the word ジュース to refer to soft drinks.
(Reference Pages: Wikipedia サイダー, ジュース )