An onion is a widely cultivated, edible bulb vegetable (Allium cepa) belonging to the amaryllis family. It is known for its concentric layered structure and pungent, sharp flavor that is utilized globally in seasoning and cooking.An onion is a widely cultivated, edible bulb vegetable (Allium cepa) belonging to the amaryllis family. It is known for its concentric layered structure and pungent, sharp flavor that is utilized globally in seasoning and cookingAn onion is a widely cultivated, edible bulb vegetable (Allium cepa) belonging to the amaryllis family. It is known for its concentric layered structure and pungent, sharp flavor that is utilized globally in seasoning and cookingAn onion is a widely cultivated, edible bulb vegetable (Allium cepa) belonging to the amaryllis family. It is known for its concentric layered structure and pungent, sharp flavor that is utilized globally in seasoning and cooking