DuckCorp Dico

Found one definition

1.                 From WordNet (r) 3.0 (2006):
                   
   
   
                   
                     
   barrier
       n 1: a structure or object that impedes free movement
       2: any condition that makes it difficult to make progress or to
          achieve an objective; "intolerance is a barrier to
          understanding" [syn: barrier, roadblock]
       3: anything serving to maintain separation by obstructing vision
          or access