Source : Webster's Revised Unabridged Dictionary (1913)

Unitary \U"nit*a*ry\, a.
   1. Of or pertaining to a unit or units; relating to unity;
      as, the unitary method in arithmetic.

   2. Of the nature of a unit; not divided; united.

   {Unitary theory} (Chem.), the modern theory that the
      molecules of all complete compounds are units, whose parts
      are bound together in definite structure, with mutual and
      reciprocal influence on each other, and are not mere
      aggregations of more or less complex groups; --
      distinguished from the dualistic theory.

Source : WordNet®

unitary
     adj 1: relating to or characterized by or aiming toward unity; "the
            unitary principles of nationalism"; "a unitary
            movement in politics"
     2: of or pertaining to or involving the use of units; "a
        unitary method was applied"; "established a unitary
        distance on which to base subsequent calculations"
     3: characterized by or constituting a form of government in
        which power is held by one central authority; "a unitary
        as opposed to a federal form of government" [ant: {federal}]
     4: having the indivisible character of a unit; "a unitary
        action"; "spoke with one voice" [syn: {one(a)}]