An onion was an edible bulb produced by the plant Allium cepa. Noted for their strong taste, onions were eaten as a vegetable and were often used to add flavour to roasts, soups, and salads.
Molly Weasley served Harry Potter a "steaming" bowl of onion soup on the first night he spent at The Burrow in 1996.
Onion juice was one of the ingredients in the ringworm-treating product Fergus Fungal Budge.
There was a magical plant called Pungous Onion, that may be related to the common variety.
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