The Collaborative International Dictionary of English v.0.48:

Moonshiner \Moon"shin`er\, n.
   A person engaged in illicit distilling; -- so called because
   the work is largely done at night. [Cant, U.S.]
   [1913 Webster]

WordNet (r) 3.0 (2006):

moonshiner
    n 1: someone who makes or sells illegal liquor [syn:
         bootlegger, moonshiner]