The Collaborative International Dictionary of English v.0.48:

Knickknackery \Knick"knack`er*y\, n.
   Knickknacks.
   [1913 Webster]

WordNet (r) 3.0 (2006):

knickknackery
    n 1: miscellaneous curios [syn: bric-a-brac, knickknack,
         nicknack, knickknackery, whatnot]