Onion

onion
    n 1: the bulb of an onion plant
    2: bulbous plant having hollow leaves cultivated worldwide for
       its rounded edible bulb [syn: {onion}, {onion plant}, {Allium
       cepa}]
    3: an aromatic flavorful vegetable
    

Onion \On"ion\, n. [F. ognon, fr. L. unio oneness, unity, a
   single large pearl, an onion. See {One}, {Union}.]
   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.
      [1913 Webster]

   2. The flavor of an onion[1].
      [PJC]

   {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}.
      [1913 Webster]
    

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."