A single yellow onion.
onion definition by Webster's New World
- a plant (Allium cepa) of the lily family, having an edible bulb with a strong, sharp smell and taste
- the bulb of this plant, formed of close, concentric layers of leaf bases
- any of various related plants
Origin: Middle English oynon ; from Old French oignon ; from Classical Latin unio (gen. unionis), oneness, unity, also a kind of single onion: see union
onion definition by American Heritage Dictionary
- A bulbous plant (Allium cepa) cultivated worldwide as a vegetable.
- The rounded edible bulb of this plant, composed of fleshy, tight, concentric leaf bases having a pungent odor and taste.
Origin: Middle English oinyon, from Old French oignon, from Latin uniō, uniōn-.