A phone tapper or wiretapper.
A weakly hit ground ball.
In early wireless telegraphs, a device used to shake loose the filings of a coherer.
A tap-dancer.
A tapster.
An assistant in the sport of paraswimming who taps blind or visually impaired swimmers with a pole to indicate when they should turn around.
One who makes a tapping noise.
The lesser spotted woodpecker.
A person who installs or monitors wiretaps.