noun
Refers to a red spherical object, or specifically to amber or jasper as gemstones. The gemstone meanings are less common in everyday use.
子供が赤玉で遊んでいる。
The child is playing with a red ball.
noun
patent medicine
Archaic term for a type of patent medicine, historically sold as a red pill or ball. Not used in modern Japanese.
江戸時代には赤玉と呼ばれる薬が売られていた。
In the Edo period, a medicine called akadama was sold.
noun
Akadama (brand of sweet wine)
Refers specifically to the brand of sweet red wine 'Akadama' (赤玉ポートワイン), well-known in Japan.
赤玉は甘口のワインで、お湯割りにして飲むこともある。
Akadama is a sweet wine, sometimes drunk mixed with hot water.