dulness

from The Collaborative International Dictionary of English v.0.48

Dullness \Dull"ness\, n.
   The state of being dull; slowness; stupidity; heaviness;
   drowsiness; bluntness; obtuseness; dimness; want of luster;
   want of vividness, or of brightness. [Written also
   {dulness}.]
   [1913 Webster]

         And gentle dullness ever loves a joke.   --Pope.
   [1913 Webster]