<botany> A herbaceous biennial liliaceous plant of the genus Allium (A.cepa), having a strong-flavoured bulb and long hollow leaves; also, its bulbous root, much used as an article of food. The name is often extended to other species of the genus.

Origin: F. Ognon, fr. L. Unio oneness, unity, a single large pearl, an onion. See One, Union.

(01 Mar 1998)