The Collaborative International Dictionary of English v.0.48:

Plebification \Pleb`i*fi*ca"tion\, n. [L. plebs the common
   people + -ficare (in comp.) to make. See -fy.]
   A rendering plebeian; the act of vulgarizing. [R.]
   [1913 Webster]

         You begin with the attempt to popularize learning . . .
         but you will end in the plebification of knowledge.
                                                  --Coleridge.
   [1913 Webster]