tailgater

noun a driver who follows too closely behind another motor vehicle
Found on https://www.encyclo.co.uk/local/20974

Tailgater

A person who swims very close to the swimmer in front of him. A tailgater tends to swim right on the feet of that swimmer.
Found on http://swim.isport.com/swimming-guides/swimming-glossary

tailgater

[n] - a driver who follows too closely behind another motor vehicle
Found on http://www.webdictionary.co.uk/definition.php?query=tailgater
No exact match found