= to drive too close behind another car

tailgate = zu dicht auffahren, drängeln

tailgate = vor einem Spiel (z. B. Fußball) auf dem Stadionparkplatz Party machen.

Sample text:

A 19 year-old driver had pot, paraphernalia, and rum in his car when he was stopped for TAILGATING and missing a traffic signal, police said.(New Jersey On-Line news portal)---Drivers across Britain who hog lanes or TAILGATE can now be punished with on-the-spot police fines of up to £100, and be issued with three points.(BBC News)