Source : Webster's Revised Unabridged Dictionary (1913)

Wad \Wad\, n. [See {Woad}.]
   Woad. [Obs.]

Wad \Wad\, n. [Probably of Scand. origin; cf. Sw. vadd wadding,
   Dan vat, D. & G. watte. Cf. {Wadmol}.]
   1. A little mass, tuft, or bundle, as of hay or tow.
      --Holland.

   2. Specifically: A little mass of some soft or flexible
      material, such as hay, straw, tow, paper, or old rope
      yarn, used for retaining a charge of powder in a gun, or
      for keeping the powder and shot close; also, to diminish
      or avoid the effects of windage. Also, by extension, a
      dusk of felt, pasteboard, etc., serving a similar purpose.

   3. A soft mass, especially of some loose, fibrous substance,
      used for various purposes, as for stopping an aperture,
      padding a garment, etc.

   {Wed hook}, a rod with a screw or hook at the end, used for
      removing the wad from a gun.

Wad \Wad\, v. t. [imp. & p. p. {Waded}; p. pr. & vb. n.
   {Wadding}.]
   1. To form into a mass, or wad, or into wadding; as, to wad
      tow or cotton.

   2. To insert or crowd a wad into; as, to wad a gun; also, to
      stuff or line with some soft substance, or wadding, like
      cotton; as, to wad a cloak.

Wad \Wad\, Wadd \Wadd\, n. (Min.)
      (a) An earthy oxide of manganese, or mixture of different
          oxides and water, with some oxide of iron, and often
          silica, alumina, lime, or baryta; black ocher. There
          are several varieties.
      (b) Plumbago, or black lead.

Source : WordNet®

wad
     n 1: (often followed by `of') a large number or amount or extent;
          "a batch of letters"; "a deal of trouble"; "a lot of
          money"; "he made a mint on the stock market"; "it must
          have cost plenty" [syn: {batch}, {deal}, {flock}, {good
          deal}, {great deal}, {hatful}, {heap}, {lot}, {mass}, {mess},
           {mickle}, {mint}, {muckle}, {peck}, {pile}, {plenty}, {pot},
           {quite a little}, {raft}, {sight}, {slew}, {spate}, {stack},
           {tidy sum}, {whole lot}, {whole slew}]
     2: a wad of something chewable as tobacco [syn: {chew}, {chaw},
         {cud}, {quid}, {plug}]
     [also: {wadding}, {wadded}]

wad
     v 1: compress into a wad; "wad paper into the box" [syn: {pack},
          {bundle}, {compact}]
     2: crowd or pack to capacity; "the theater was jampacked" [syn:
         {jam}, {jampack}, {ram}, {chock up}, {cram}]
     [also: {wadding}, {wadded}]