- any bulbous plant belonging to the genus Allium, of the amaryllis family, having an onion odor and flowers in a round cluster, including the onion, leek, shallot, garlic, and chive.
- a substance occurring in garlic bulbs that has antibiotic properties.
- any plant of the genus Allium, such as the onion, garlic, shallot, leek, or chive: family Alliaceae
