rubberneck
Concise Oxford English Dictionary © 2008 Oxford University Press:
rubberneck /ˈrʌbənek/ informal
▶verb turn one's head to stare at something in a foolish manner. ▶noun a person who stares in this way.
– derivatives
rubbernecker noun.
rubbernecker noun.
'rubberneck' also found in these Oxford entries:

