Source : Webster's Revised Unabridged Dictionary (1913)

Smack \Smack\, v. i. [imp. & p. p. {Smacked}; p. pr. & vb. n.
   {Smacking}.] [OE. smaken to taste, have a taste, -- from the
   noun; cf. AS. smecan taste; akin to D. smaken, G. schmecken,
   OHG. smechen to taste, smach?n to have a taste (and, derived
   from the same source, G. schmatzen to smack the lips, to kiss
   with a sharp noise, MHG. smatzen, smackzeen), Icel smakka to
   taste, Sw. smaka, Dan. smage. See 2d {Smack}, n.]
   1. To have a smack; to be tinctured with any particular
      taste.

   2. To have or exhibit indications of the presence of any
      character or quality.

            All sects, all ages, smack of this vice. --Shak.

   3. To kiss with a close compression of the lips, so as to
      make a sound when they separate; to kiss with a sharp
      noise; to buss.

   4. To make a noise by the separation of the lips after
      tasting anything.

Smacking \Smack"ing\, n.
   A sharp, quick noise; a smack.

         Like the faint smacking of an after kiss. --Dryden.

Smacking \Smack"ing\, a.
   Making a sharp, brisk sound; hence, brisk; as, a smacking
   breeze.

Source : WordNet®

smacking
     n : the act of smacking something; a blow delivered with an open
         hand [syn: {smack}, {slap}]