The Collaborative International Dictionary of English v.0.48:

Delimitation \De*lim`i*ta"tion\, n. [L. delimitatio: cf. F.
   d['e]limitation.]
   The act or process of fixing limits or boundaries;
   limitation. --Gladstone.
   [1913 Webster]

WordNet (r) 3.0 (2006):

delimitation
    n 1: a line that indicates a boundary [syn: boundary line,
         border, borderline, delimitation, mete]