from
The Collaborative International Dictionary of English v.0.48
Tun \Tun\ (t[u^]n), n. [AS. tunne. See {Ton} a weight.]
1. A large cask; an oblong vessel bulging in the middle, like
a pipe or puncheon, and girt with hoops; a wine cask.
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2. (Brewing) A fermenting vat.
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3. A certain measure for liquids, as for wine, equal to two
pipes, four hogsheads, or 252 gallons. In different
countries, the tun differs in quantity.
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4. (Com.) A weight of 2,240 pounds. See {Ton}. [R.]
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5. An indefinite large quantity. --Shak.
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A tun of man in thy large bulk is writ. --Dryden.
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6. A drunkard; -- so called humorously, or in contempt.
--Dryden.
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7. (Zool.) Any shell belonging to {Dolium} and allied genera;
-- called also {tun-shell}.
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