The Collaborative International Dictionary of English v.0.48:

Rag \Rag\, n. [OE. ragge, probably of Scand, origin; cf. Icel.
   r["o]gg a tuft, shagginess, Sw. ragg rough hair. Cf. Rug,
   n.]
   1. A piece of cloth torn off; a tattered piece of cloth; a
      shred; a tatter; a fragment.
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            Cowls, hoods, and habits, with their wearers,
            tossed,
            And fluttered into rags.              --Milton.
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            Not having otherwise any rag of legality to cover
            the shame of their cruelty.           --Fuller.
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   2. pl. Hence, mean or tattered attire; worn-out dress.
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            And virtue, though in rags, will keep me warm.
                                                  --Dryden.
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   3. A shabby, beggarly fellow; a ragamuffin.
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            The other zealous rag is the compositor. --B.
                                                  Jonson.
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            Upon the proclamation, they all came in, both tag
            and rag.                              --Spenser.
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   4. (Geol.) A coarse kind of rock, somewhat cellular in
      texture.
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   5. (Metal Working) A ragged edge.
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   6. A sail, or any piece of canvas. [Nautical Slang]
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            Our ship was a clipper with every rag set. --Lowell.
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   Rag bolt, an iron pin with barbs on its shank to retain it
      in place.

   Rag carpet, a carpet of which the weft consists of narrow
      strips of cloth sewed together, end to end.

   Rag dust, fine particles of ground-up rags, used in making
      papier-mach['e] and wall papers.

   Rag wheel.
      (a) A chain wheel; a sprocket wheel.
      (b) A polishing wheel made of disks of cloth clamped
          together on a mandrel.

   Rag wool, wool obtained by tearing woolen rags into fine
      bits, shoddy.
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