DuckCorp Dico

Found one definition

1.                 From WordNet (r) 3.0 (2006):
                   
   
   
                   
                     
   tapper
       n 1: a tavern keeper who taps kegs or casks [syn: tapster,
            tapper]
       2: a person who strikes a surface lightly and usually
          repeatedly; "finger tappers irritated her"
       3: a worker who uses a tap to cut screw threads
       4: someone who wiretaps a telephone or telegraph wire [syn:
          tapper, wiretapper, phone tapper]
       5: a dancer who sounds out rhythms by using metal taps on the
          toes and heels of the shoes [syn: tap dancer, tapper]