Karaimo - Spicy potato

Japanese: カライモ - からいも

...The potato, which is very similar to the yam, is called tokoro (old man), and is no longer eaten, but appears as an offering at shrine festivals and annual events. The sweet potato is also called karaimo, touimo, or ryukyuuimo, indicating that it is an imported potato, but its introduction enriched the Japanese diet and saved them from famine, so monuments to its introduction have been erected in various places. In Hokkaido, the potato is called imo, but in Honshu, it is a new potato and has many other names. ...

From [Sweet potato (Satsuma potato)]

…It is also called kansho (sweet potato), ryukyu-imo (Ryukyu potato), or karaimo (Chinese potato). It is a perennial plant of the Convolvulaceae family cultivated for its swollen roots, which are used for food and as a source of starch (illustration).

*Some of the terminology explanations that mention "Karaimo" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

Japanese:

…ヤマノイモとよく似たトコロ(野老)と呼ぶいもは，今では食べないが，神社の祭りや年中行事などに供え物として登場してくる。サツマイモはカライモ，トウイモ，リュウキュウイモとも呼ばれ，外来のいもであることを示しているが，このいもの伝来によって日本人の食生活は豊かとなり，飢饉からも救われたため，各地に伝来の記念碑が建てられている。ジャガイモを北海道ではいもと呼ぶが，本州では新しいいものため異名が多い。…