noun
A variety of runner bean with purple flowers and seeds, cultivated for its edible beans.
紫花豆は煮豆や甘納豆に使われることが多い。
Scarlet runner beans are often used for simmered beans or sweetened beans.
花豆 is a broader term for runner beans, while 紫花豆 specifically refers to the purple-flowered variety.
Compound of 紫 (murasaki, 'purple'), 花 (hana, 'flower'), and 豆 (mame, 'bean'), referring to the plant's purple flowers.