Answer: rubbernecker

AnswerCrossword Clue
RUBBERNECKERMotoring menace
RUBBERNECKERTraffic-accident gawker
RUBBERNECKEROne gawking at traffic
RUBBERNECKEROne who might cause a traffic tie-up near an accident
rubberneckerRUBBERNECK, to look curiously at something