Wiktionary
n. 1 (context countable uncountable English) A form of cabbage having red leaves, (taxlink Brassica oleracea var. capitata f. rubra form noshow=1) . 2 (context uncountable English) Food made from the leaves of the plant.
WordNet
n. cabbage plant with a compact head of reddish purple leaves
compact head of purplish-red leaves
Wikipedia
The red cabbage (purple-leaved varieties of Brassica oleracea Capitata Group) is a kind of cabbage, also known as purple cabbage, red kraut, or blue kraut after preparation. Its leaves are coloured dark red/purple. However, the plant changes its colour according to the pH value of the soil, due to a pigment belonging to anthocyanins. In acidic soils, the leaves grow more reddish, in neutral soils they will grow more purple, while an alkaline soil will produce rather greenish-yellow coloured cabbages. This explains the fact that the same plant is known by different colours in various regions. Furthermore, the juice of red cabbage can be used as a home-made pH indicator, turning red in acid and green/yellow in basic solutions. It can be found in Northern Europe, throughout the Americas, and in China.
On cooking, red cabbage will normally turn blue. To retain the red colour it is necessary to add vinegar or acidic fruit to the pot.
Red cabbage needs well fertilized soil and sufficient humidity to grow. It is a seasonal plant which is seeded in spring and harvested in late fall. Red cabbage is a better keeper than its "white" relatives and does not need to be converted to sauerkraut to last the winter.
Usage examples of "red cabbage".
There were five slices: red cabbage, onions, leeks, carrots, and turnips.
He took his nasty old book away and leafed expressionlessly through the pages, leaving me standing amid potatoes and several representatives of the cabbage family, white cabbage, red cabbage, savoy cabbage, Brussels sprouts, and kohlrabi, wretchedly lonely, for I had left my drum at home.
A surprise, someting special and delicious, he averred, wit red cabbage.
My mother had the fried chicken on the table, along with biscuits and red cabbage and broccoli.
He got himself an excellent roast duck, an enormous mound of red cabbage, and all the fine lager he could drink for the price of a couple of apples back in Poland.