The Collaborative International Dictionary of English v.0.48:

Spigot \Spig"ot\, n. [From spick,or spike; cf. Ir. & Gael.
   spiocaid a spigot, Ir. spice a spike. See Spike.]
   A pin or peg used to stop the vent in a cask; also, the plug
   of a faucet or cock.
   [1913 Webster]

   Spigot and faucet joint, a joint for uniting pipes, formed
      by the insertion of the end of one pipe, or pipe fitting,
      into a socket at the end of another.
      [1913 Webster]

WordNet (r) 3.0 (2006):

spigot
    n 1: a plug for a bunghole in a cask [syn: tap, spigot]
    2: a regulator for controlling the flow of a liquid from a
       reservoir [syn: faucet, spigot]

Moby Thesaurus II by Grady Ward, 1.0:

31 Moby Thesaurus words for "spigot":
   ball cock, ball valve, bung, bunghole, check valve, cock, cork,
   drain cock, draw cock, faucet, gate, hydrant, lid, needle valve,
   peg, petcock, pin, plug, sea cock, spike, spile, spill, stop,
   stopcock, stopgap, stopper, stopple, tap, valve, valvula,
   valvule