Choy sum Choy sum Choy sum (also spelled choi sum or "Cai Xin" in modern Pinyin) is a leafy vegetable commonly used in Chinese cuisine. It is a member of the genus "Brassica" of the mustard family, Brassicaceae ("Brassica rapa" var. "parachinensis" or "Brassica chinensis" var. "parachinensis"). Choy sum is a transliteration of the Cantonese name (), which can be literally translated as "heart of the vegetable". It is also known as Chinese Flowering Cabbage. Choy sum is a green leafy vegetable similar to gai lan, and can be characterized by the distinct yellow flowers which it bears. Each flower has four
Vegetable meaning then being "the edible part of such a plant". A more precise definition is "any plant part consumed for food that is not a fruit or seed, but including mature fruits that are eaten as part of a main meal". Falling outside these definitions are edible fungi (such as edible mushrooms) and edible seaweed which, although not parts of plants, are often treated as vegetables. In the latter-mentioned definition of "vegetable", which is used in everyday language, the words "fruit" and "vegetable" are mutually exclusive. "Fruit" has a precise botanical meaning, being a part that developed from the ovary