{i} sharp-tasting edible bulb consisting of concentric fleshy layers (used much in cooking); any of various bulbous hollow-leaved plants which are cultivated for their sharp-tasting edible bulb
An onion is a round vegetable with a brown skin that grows underground. It has many white layers on its inside which have a strong, sharp smell and taste. It is made with fresh minced meat, cooked with onion and a rich tomato sauce. Herbaceous biennial plant (Allium cepa) of the lily family, probably native to South Asia but now grown worldwide, and its edible bulb. Among the hardiest and oldest garden-vegetable plants, onions bear a cluster of small, greenish white flowers on one or more leafless stalks. The leaf base swells to form the underground mature edible onion. Onions are pungent; because they contain a sulfur-rich volatile oil, peeling or slicing them can cause a person's eyes to tear. Onions vary in size, shape, colour, and pungency. Though low in standard nutrients, they are valued for their flavour. Onions have been claimed to cure colds, earaches, and laryngitis and have been used to treat animal bites, powder burns, and warts; like their close relative garlic, they are being studied for other suspected beneficial qualities. See also allium
This underground bulb is related to leeks, garlic, and chives and is prized for its distinct, pungent flavor and aroma There are two types: green ("scallions") and dry onions The white-skinned onion has the mildest flavor of the onions