köken: Ultimately from Persian خمباره (xombâra) (compare modern Persian خمپاره (xompâre)); probably via Ottoman Turkish خمبره (humbara, kumbara). The athletic sense is probably a more recent semantic loan from Russian ядро́ (jadró).
köken: Probably a compound of 手 (shu, “hand”) + 榴弾 (ryūdan, “explosive shell”). First cited with this reading to a text from 1922. It remains unclear whether this term was coined in Japanese originally, and then borrowed into Chinese and Korean, or if it was coined in Chinese originally, and borrowed into Japanese and Korean.