Source : Webster's Revised Unabridged Dictionary (1913)

Dozen \Doz"en\, n.; pl. {Dozen} (before another noun), {Dozens}.
   [OE. doseine, dosein, OF. doseine, F. douzaine, fr. douze
   twelve, fr. L. duodecim; duo two + decem ten. See {Two},
   {Ten}, and cf. {Duodecimal}.]
   1. A collection of twelve objects; a tale or set of twelve;
      with or without of before the substantive which follows.
      ``Some six or seven dozen of Scots.'' ``A dozen of shirts
      to your back.'' ``A dozen sons.'' ``Half a dozen
      friends.'' --Shak.

   2. An indefinite small number. --Milton.

   {A baker's dozen}, thirteen; -- called also a {long dozen}.

Dozen \Doz"en\, n.; pl. {Dozen} (before another noun), {Dozens}.
   [OE. doseine, dosein, OF. doseine, F. douzaine, fr. douze
   twelve, fr. L. duodecim; duo two + decem ten. See {Two},
   {Ten}, and cf. {Duodecimal}.]
   1. A collection of twelve objects; a tale or set of twelve;
      with or without of before the substantive which follows.
      ``Some six or seven dozen of Scots.'' ``A dozen of shirts
      to your back.'' ``A dozen sons.'' ``Half a dozen
      friends.'' --Shak.

   2. An indefinite small number. --Milton.

   {A baker's dozen}, thirteen; -- called also a {long dozen}.

Source : WordNet®

dozen
     adj : denoting a quantity consisting of 12 items or units [syn: {twelve},
            {12}, {xii}]
     n : the cardinal number that is the sum of eleven and one [syn:
         {twelve}, {12}, {XII}]