Source : Webster's Revised Unabridged Dictionary (1913)

Determiner \De*ter"min*er\, n.
   One who, or that which, determines or decides.

Source : WordNet®

determiner
     n 1: an argument that is conclusive [syn: {clincher}, {determining
          factor}]
     2: one of a limited class of noun modifiers that determine the
        referents of noun phrases [syn: {determinative}]
     3: a determining or causal element or factor; "education is an
        important determinant of one's outlook on life" [syn: {determinant},
         {determinative}, {determining factor}, {causal factor}]