Source : Webster's Revised Unabridged Dictionary (1913)

Smack \Smack\, adv.
   As if with a smack or slap. [Colloq.]

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.

Smack \Smack\, n. [D. smak; akin to LG. smack, smak, Dan.
   smakke, G. schmacke, F. semaque.] (Naut.)
   A small sailing vessel, commonly rigged as a sloop, used
   chiefly in the coasting and fishing trade.

Smack \Smack\, n. [OE. smak, AS. ssm?c taste, savor; akin to D.
   smaak, G. geschmack, OHG. smac; cf. Lith. smagus pleasant.
   Cf. {Smack}, v. i.]
   1. Taste or flavor, esp. a slight taste or flavor; savor;
      tincture; as, a smack of bitter in the medicine. Also used
      figuratively.

            So quickly they have taken a smack in covetousness.
                                                  --Robynson
                                                  (More's
                                                  Utopia).

            They felt the smack of this world.    --Latimer.

   2. A small quantity; a taste. --Dryden.

   3. A loud kiss; a buss. ``A clamorous smack.'' --Shak.

   4. A quick, sharp noise, as of the lips when suddenly
      separated, or of a whip.

   5. A quick, smart blow; a slap. --Johnson.

Smack \Smack\, v. t.
   1. To kiss with a sharp noise; to buss.

   2. To open, as the lips, with an inarticulate sound made by a
      quick compression and separation of the parts of the
      mouth; to make a noise with, as the lips, by separating
      them in the act of kissing or after tasting.

            Drinking off the cup, and smacking his lips with an
            air of ineffable relish.              --Sir W.
                                                  Scott.

   3. To make a sharp noise by striking; to crack; as, to smack
      a whip. ``She smacks the silken thong.'' --Young.

Source : WordNet®

smack
     n 1: a blow from a flat object (as an open hand) [syn: {slap}]
     2: the taste experience when a savoury condiment is taken into
        the mouth [syn: {relish}, {flavor}, {flavour}, {sapidity},
         {savor}, {savour}, {tang}]
     3: a sailing ship (usually rigged like a sloop or cutter) used
        in fishing and sailing along the coast
     4: street names for heroin [syn: {big H}, {hell dust}, {nose
        drops}, {thunder}]
     5: an enthusiastic kiss [syn: {smooch}]
     6: the act of smacking something; a blow delivered with an open
        hand [syn: {smacking}, {slap}]
     adv : directly; "he ran bang into the pole"; "ran slap into her"
           [syn: {bang}, {slap}, {slapdash}, {bolt}]
     v 1: deliver a hard blow to; "The teacher smacked the student who
          had misbehaved" [syn: {thwack}]
     2: have an element suggestive (of something); "his speeches
        smacked of racism" [syn: {reek}]
     3: have a distinctive or characteristic taste; "This tastes of
        nutmeg" [syn: {taste}]
     4: kiss lightly [syn: {peck}]
     5: eat noisily by smacking one's lips