The common English name for the Chinese cabbage with white stalks is bok choy. It is a leafy vegetable in the species Brassica rapa, with dark green leaves and pale, crisp stalks that form a loose cluster rather than a tightly closed head.
Bok choy is the North American spelling of a Cantonese-derived name. Pak choi and pak choy are common variants, especially in Britain, South Africa, and the Caribbean. The name refers to a white vegetable, describing the light-colored stalks and bases.
There are several forms, including white bok choy, green bok choy, and baby bok choy. White bok choy is particularly associated with southern China, while green-stemmed varieties are more common in parts of eastern China. The leaves cook faster than the stalks, so stir-frying often begins with the stems.
A frequent mix-up is napa cabbage. Napa cabbage has elongated, tightly packed heads, while bok choy does not form a head. Celery, kale, and choy sum are related culinary comparisons but are different vegetables.