Definition of "tapper"

tapper

noun
plural tappers
1. One who makes a tapping noise.
  Quotations
  A low tap was heard at the room door. Mr. Bob Sawyer looked expressively at his friend, and bade the tapper come in […]
  1836 March – 1837 October, Charles Dickens, “(please specify the chapter name)”, in The Posthumous Papers of the Pickwick Club, London: Chapman and Hall, […], published 1837
2. A tap-dancer.
3. A phone tapper or wiretapper.
4. (baseball slang) A weakly hit ground ball.
5. (telegraphy) In early wireless telegraphs, a device used to shake loose the filings of a coherer.
6. (Britain, dialect) The lesser spotted woodpecker.
7. (US) A tapster.
8. (sports) An assistant in the sport of paraswimming who taps blind or visually impaired swimmers with a pole to indicate when they should turn around.