onion
  洋蔥
  On·ion n.
  1. Bot. A liliaceous plant of the genus Allium (Allium cepa), having a strong-flavored 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.
  Onion fish Zool., the grenadier.
  Onion fly Zool. a dipterous insect whose larva feeds upon the onion; especially, Anthomyia ceparum and Ortalis flexa.
  Welsh onion. Bot. See Cibol.
  Wild onion Bot., a name given to several species of the genus Allium.
  ◄ ►
  onion
       n 1: edible bulb of an onion plant
       2: bulbous plant having hollow leaves cultivated worldwide for
          its rounded edible bulb [syn: onion plant, Allium cepa]
       3: an aromatic flavorful bulb
  Onion
     The Israelites in the wilderness longed for the "onions and
     garlick of Egypt" (Num. 11:5). This was the _betsel_ of the
     Hebrews, the Allium cepe of botanists, of which it is said that
     there are some thirty or forty species now growing in Palestine.
     The onion is "the 'undivided' leek, _unio_, _unus_, one."