The Collaborative International Dictionary of English v.0.48:

Rub \Rub\, v. t. [imp. & p. p. Rubbed; p. pr. & vb. n.
   Rubbing.] [Probably of Celtic origin; cf. W. rhwbiaw, gael.
   rub.]
   1. To subject (a body) to the action of something moving over
      its surface with pressure and friction, especially to the
      action of something moving back and forth; as, to rub the
      flesh with the hand; to rub wood with sandpaper.
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            It shall be expedient, after that body is cleaned,
            to rub the body with a coarse linen cloth. --Sir T.
                                                  Elyot.
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   2. To move over the surface of (a body) with pressure and
      friction; to graze; to chafe; as, the boat rubs the
      ground.
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   3. To cause (a body) to move with pressure and friction along
      a surface; as, to rub the hand over the body.
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            Two bones rubbed hard against one another.
                                                  --Arbuthnot.
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   4. To spread a substance thinly over; to smear.
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            The smoothed plank, . . .
            New rubbed with balm.                 --Milton.
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   5. To scour; to burnish; to polish; to brighten; to cleanse;
      -- often with up or over; as, to rub up silver.
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            The whole business of our redemption is to rub over
            the defaced copy of the creation.     --South.
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   6. To hinder; to cross; to thwart. [R.]
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            'T is the duke's pleasure,
            Whose disposition, all the world well knows,
            Will not be rubbed nor stopped.       --Shak.
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   To rub down.
      (a) To clean by rubbing; to comb or curry; as, to down a
          horse.
      (b) To reduce or remove by rubbing; as, to rub down the
          rough points.

   To rub off, to clean anything by rubbing; to separate by
      friction; as, to rub off rust.

   To rub out, to remove or separate by friction; to erase; to
      obliterate; as, to rub out a mark or letter; to rub out a
      stain.

   To rub up.
      (a) To burnish; to polish; to clean.
      (b) To excite; to awaken; to rouse to action; as, to rub
          up the memory.
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