taro, yam, tuber
芋 centers on starchy underground vegetables: taro, yams, and other edible tubers.
芋 combines the plant radical 艹 with 于, which likely contributes a phonetic element. The character originally referred to taro or similar tubers.
The plant top 艹 sits above 于, like leafy greens growing above a round tuber hidden underground.
For ウ, imagine pulling a taro out of the earth with a satisfying 'oo!' sound: 'oo!' -> ウ, as you uncover the tuber.
tuber; taro; potato; yam
potato (Solanum tuberosum)
sweet potato (Ipomoea batatas)
roasted sweet potato; baked sweet potato
imoni (taro and meat soup)
hornworm (caterpillar of a hawk moth); (hairless) caterpillar
taro (Colocasia esculenta); dasheen; eddo
Japanese yam (Dioscorea japonica)
Chinese yam (Dioscorea batatas)
sweet-potato vines
calla (Zantedeschia aethiopica)
taro (Colocasia esculenta); cocoyam; dasheen
seed potato
variety of acrid-tasting taro
yam
steamed potato (esp. sweet potato)
potato bean (Apios americana); hog peanut; hopniss; Indian potato; groundnut; ground pea
potato (Solanum tuberosum)
type of taro originally from Sulawesi
lesser yam (Dioscorea esculenta)