Merriam-Webster Collegiate Dictionary - puncheon

 I. noun  Etymology: Middle English ponson, punchon, from Anglo-French ponchon pointed tool, support, ultimately from Vulgar Latin *punctiare to prick, pierce, from Latin punctum, supine of pungere — more at pungent  Date: 14th century  1. a pointed tool for piercing or for working on stone  2.  a. a short upright framing timber  b. a split log or heavy slab with the face smoothed  II. noun  Etymology: Middle English punchon, from Anglo-French ponchon, probably from Middle French poincon mark on goods certifying their origin  Date: 15th century a large cask of varying capacity