Source : Webster's Revised Unabridged Dictionary (1913)

Cliquish \Cli"quish\, a.
   Of or pertaining to a clique; disposed to from cliques;
   exclusive in spirit. -- {Cli"*quish*ness}, n.

Source : WordNet®

cliquishness
     n : tendency to associate with only a select group [syn: {clannishness},
          {exclusiveness}]