1Chinese cabbage, esp. napa cabbage (Brassica rapa subsp. pekinensis)
2sometimes used to refer to bok choy (Brassica rapa subsp. chinensis)
Example
zhè這me麼dà大de的bái cài白菜zhǔ煮shú熟liǎo了jìu就biàn變zhè這me麼xiǎo小liǎo了。
這麼大的白菜煮熟了就變這麼小了。
The cabbage that was this big becomes this small after being cooked.