The Collaborative International Dictionary of English v.0.48:

Puncheon \Punch"eon\, n. [F. poin[,c]on awl, bodkin, crown,
   king-post, fr. L. punctio a pricking, fr. pungere to prick.
   See Pungent, and cf. Punch a tool, Punction.]
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   1. A figured stamp, die, or punch, used by goldsmiths,
      cutlers, etc.
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   2. (Carp.) A short, upright piece of timber in framing; a
      short post; an intermediate stud. --Oxf. Gloss.
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   3. A split log or heavy slab with the face smoothed; as, a
      floor made of puncheons. [U.S.] --Bartlett.
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   4. [F. poin[,c]on, perh. the same as poin[,c]on an awl.] A
      cask containing, sometimes 84, sometimes 120, gallons.
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