The Collaborative International Dictionary of English v.0.48:

Dab \Dab\ (d[a^]b), v. i. [imp. & p. p. Dabbed (d[a^]bd); p.
   pr. & vb. n. Dabbing.] [OE. dabben to strice; akin to OD.
   dabben to pinch, knead, fumble, dabble, and perh. to G.
   tappen to grope.]
   1. To strike or touch gently, as with a soft or moist
      substance; to tap; hence, to besmear with a dabber.
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            A sore should . . . be wiped . . . only by dabbing
            it over with fine lint.               --S. Sharp.
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   2. To strike by a thrust; to hit with a sudden blow or
      thrust. "To dab him in the neck." --Sir T. More.
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