Source : Webster's Revised Unabridged Dictionary (1913)

Definitive \De*fin"i*tive\, a. [L. definitivus: cf. F.
   d['e]finitif.]
   1. Determinate; positive; final; conclusive; unconditional;
      express.

            A strict and definitive truth.        --Sir T.
                                                  Browne.

            Some definitive . . . scheme of reconciliation.
                                                  --Prescott.

   2. Limiting; determining; as, a definitive word.

   3. Determined; resolved. [Obs.] --Shak.

Definitive \De*fin"i*tive\, n. (Gram.)
   A word used to define or limit the extent of the
   signification of a common noun, such as the definite article,
   and some pronouns.

   Note: Definitives . . . are commonly called by grammarians
         articles. . . . They are of two kinds, either those
         properly and strictly so called, or else pronominal
         articles, such as this, that, any, other, some, all,
         no, none, etc. --Harris (Hermes).

Source : WordNet®

definitive
     adj 1: clearly defined or formulated; "the plain and unequivocal
            language of the laws"- R.B.Taney [syn: {unequivocal}]
     2: of recognized authority or excellence; "the definitive work
        on Greece"; "classical methods of navigation" [syn: {authoritative},
         {classical}]
     3: supplying or being a final or conclusive settlement; "a
        definitive verdict"; "a determinate answer to the problem"
        [syn: {determinate}]